SciPost: SciPost Physics Proceedings: issue detail

SciPost Physics Proceedings issue 13

21st International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI2022)

Event dates: from 2022-05-23 to 2022-05-28.

The 21st International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2020) was to have been hosted by the GRAPES-3 Collaboration at the Cosmic Ray Laboratory, Tata Institute of Fundamental Research (TIFR) in Ooty, India during 4-8 June 2020. However, the outbreak of the Covid-19 pandemic prevented that and the symposium was postponed to a later date. It was finally decided to hold the Symposium virtually from 23-28 May 2022 (renamed ISVHECRI 2022) under the auspices of the International Union of Pure and Applied Physics (IUPAP).

ISVHECRI is a biennial conference series launched in 1980 at Nakhodka (Russia) dedicated to cosmic ray research. A specific aspect of the ISVHECRI series is to focus on high energy collisions of cosmic ray particles and related topics, including all aspects of high energy cosmic ray physics. These Symposia also highlight the accelerator studies of hadronic interactions at very high energies and the concomitant interpretation of the cosmic ray data.

Since 2002 this series has brought together cosmic ray physicists and scientists involved with high energy accelerators, including the LHC and RHIC. The previous two meetings held at CERN in 2014 and Moscow in 2016 were ideal opportunities for cosmic-ray and particle physicists engaged in accelerator experiments to directly discuss problems of mutual interest, following the successful start-up of the Large Hadron Collider. The Nagoya 2018 Symposium extended the scope of interests to the production of neutrinos and gamma-rays in the atmosphere or in interstellar space, inspired by recent rapid progress in multi-messenger astrophysics, and this continues with ISVHECRI 2022.

Topics covered in this Symposium
• High energy astroparticle physics results relevant to particle physics
• Space experiment results relevant to high energy interactions
•Accelerator experiments relevant to cosmic ray physics
• Exotic phenomena & searches for new physics beyond the Standard Model
• LHC pp & heavy ion physics
• Cross-sections and interaction models
• High energy neutrinos and muons, including the muon puzzle
• Multi-messenger cosmic ray observations & interpretations
• Simulation tools for cosmic ray & neutrino physics
• Future accelerators & cosmic ray experiments

The Symposium consisted of plenary sessions including invited and contributed talks. A special session was convened to discuss in depth the "Cosmic Muon Puzzle’' revealed by air shower arrays. Prof. Takaaki Kajita, Chair C4, was invited to deliver a public lecture as part of the academic outreach during ISVHECRI 2022.

The complete Timetable and Speakers’ slides may be found on the Symposium website https://indico.tifr.res.in/indico/event/isvhecri2022.

We wish to thank the International Advisory Committee, the Scientific Program Committee, the Local Organizing Committee, and all the speakers who made this a very successful meeting. Thanks are also due to the TIFR administration for their generous support.

(Guest) Fellows responsible for this Issue

Dr Hariharan Balakrishnan
Dr J Bryan M Pattison
Prof. Subir Sarkar

Foreword by Prof. Sunil K. Gupta (click to expand/collapse)

On behalf of the International Advisory Committee (IAC), it is my privilege and honour to extend a warm welcome to the participants of the 21st International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI-2022). This symposium is being organised at the Tata Institute of Fundamental Research (TIFR) Mumbai after the original plan to host it in April 2020 at Ooty had to be postponed due to the Covid-19 pandemic. This multi-disciplinary symposium spans three areas of research which include cosmic ray physics, nuclear physics and high-energy physics the areas that TIFR also engages in. In this context, it is satisfying to learn that TIFR would accord greater autonomy to the Cosmic Ray Laboratory (CRL) in Ooty by transforming it into a National Cosmic Ray Centre. This should significantly enhance the physics impact of its flagship GRAPES-3 experiment. The GRAPES-3 is a growing collaboration of Indian and Japanese groups which in addition to the development and large-scale production of particle detectors has also made important contributions in the emerging areas of space weather and atmospheric sciences. Another landmark event occurred on 31 March 2022, when Prof. T. Kajita, Director of the Institute for Cosmic Ray Research in Japan and Prof. S. Ramakrishnan, Director, TIFR signed a Memorandum of Cooperation to further enhance scientific exchange and cooperation between Japan and India in the areas of cosmic rays and astroparticle physics.

TIFR has a tradition of inviting eminent scientists to serve as Honorary Fellows, and from time-to-time to seek their counsel on the areas and direction of research to be pursued. It is a source of great pleasure that two of the Honorary Fellows, namely, Prof. T. Kajita and Prof. S.C.C. Ting are delivering invited talks during ISVHECRI-2022. I once again extend a warm welcome to all of the participants who are physically present as well as those joining remotely.

Unfortunately, 20 February 2022 witnessed the passing away of one of the pioneers of our field, a dear friend and colleague Professor Thomas Korff Gaisser, Martin Pomerantz Professor Emeritus of Physics at the University of Delaware, USA. I have so many wonderful memories of interactions with Tom, spanning the past 34 years that I can not help but share at least some of them with the participants of this symposium. I first met Tom in 1988 at ICTP in Trieste, Italy when I attended a summer school where he lectured. I used to ask a lot of questions to improve my understanding of the subject. Sometimes, he would reply that “let me think it over and I would discuss it tomorrow”. A few days before he left, Tom asked if I would spend a few months with his group in the USA. Due to several constraints I had to decline his generous offer. In hindsight, I can safely state that that was certainly not a smart decision as the people who worked with him all became leaders in our field! Of course, the ever gracious Tom remained a warm and trusted friend.

Tom served our community for 12 long years through the IUPAP by being a member, Secretary, Vice-Chair and the Chair of Commission C4 on Cosmic Rays (now Astroparticle Physics). He was recognized by his peers for his outstanding scientific contribution with the award of the O’Ceallaigh medal and finally during the 34th ICRC in Busan, South Korea by the Homi Bhabha medal and prize. A condition for this award is that the winner is invited to visit the TIFR, Mumbai and CRL, Ooty to deliver a public lecture at each venue. Tom’s lectures were massively popular attracting 1000 and 600 participants in Mumbai and Ooty, respectively. Major Indian national newspapers (circulation in millions) interviewed him and prominently reported.

His monograph on Cosmic Rays is a masterpiece and remains an indispensable tool in the armoury of every aspiring and seasoned cosmic ray physicist. He along with late Prof Martin Pomerantz was the prime mover behind the creation of the Shakti P. Duggal prize in 1983 to recognize young scientists which became the first international award in our field. I had highly rewarding and memorable interactions with Tom especially during my work as the Chair, C4. He selflessly served as a member of the International Scientific Program Committee (SPC) for the past several ICRCs. He had absolutely no qualms about working in the committees chaired by people far less experienced and/or accomplished than him. He was among the founding members of ISVHECRI series of symposia where he was a constant presence. As a member of the IAC, he handsomely contributed to the present edition as well. Sadly his untimely passing has robbed us of his future counsel, a view shared by the members of IAC and SPC. The inaugural session of this symposium provided the perfect venue to pay respects to this great yet humble physicist, teacher, mentor and colleague. Several of Tom’s colleagues including Ralph Engel, Takaaki Kajita, Paolo Lipari, Subir Sarkar, Alan Watson, and several others shared their recollections of this outstanding colleague. It was especially poignant that Tom’s wife and one of his collaborator Julia Gaisser joined online. Tom Gaisser will not be forgotten.

Sunil K. Gupta
Co-Chair, IAC

Tom Gaisser. Copyright: Cosmic Ray Laboratory, Ooty, India.

Proton penetration efficiency over a high altitude observatory in Mexico

S. Miyake, T. Koi, Y. Muraki, Y. Matsubara, S. Masuda, P. Miranda, T. Naito, E. Ortiz, A. Oshima, T. Sakai, T. Sako, S. Shibata, H. Takamaru, M. Tokumaru, J. F. Valdés-Galicia

SciPost Phys. Proc. 13, 001 (2023) · published 28 September 2023 | · pdf

In association with a large solar flare on November 7, 2004, the solar neutron detectors located at Mt. Chacaltaya (5,250 m) in Bolivia and Mt. Sierra Negra (4,600 m) in Mexico recorded very interesting events. In order to explain these events, we have performed a calculation solving the equation of motion of anti-protons inside the magnetosphere. Based on these results, the Mt. Chacaltaya event may be explained by the detection of solar neutrons, while the Mt. Sierra Negra event may be explained by the first detection of very high energy solar neutron decay protons (SNDPs) around 6 GeV.
Cosmic ray measurements with IceCube and IceTop

Dennis Soldin (for the IceCube Collaboration)

SciPost Phys. Proc. 13, 002 (2023) · published 28 September 2023 | · pdf

IceCube is a cubic-kilometer Cherenkov detector in the deep ice at the geographic South Pole. The dominant event yield in the deep ice detector consists of penetrating atmospheric muons with energies above approximately 300 GeV, produced in cosmic ray air showers. In addition, the surface array, IceTop, measures the electromagnetic component and GeV muons of air showers. Hence, IceCube and IceTop yield unique opportunities to study cosmic rays with unprecedented statistics in great detail. We will present recent results of comic ray measurements from IceCube and IceTop. In this overview, we will highlight measurements of the energy spectrum of cosmic rays from 250 TeV up to the EeV range and their mass composition above 3 PeV. We will also report recent results from measurements of the muon content in air showers and discuss their consistency with predictions from current hadronic interaction models.
Muon puzzle in inclined muon bundles detected by NEVOD-DECOR

A. G. Bogdanov, N. S. Barbashina, S. S. Khokhlov, V. V. Kindin, R. P. Kokoulin, K. G. Kompaniets, A. Y. Konovalova, G. Mannocchi, A. A. Petrukhin, V. V. Shutenko, G. Trinchero, V. S. Vorobev, I. I. Yashin, E. A. Yurina, E. A. Zadeba

SciPost Phys. Proc. 13, 003 (2023) · published 28 September 2023 | · pdf

The data of cosmic ray NEVOD-DECOR experiment on the investigation of inclined muon bundles for a long time period (May 2012 - March 2021) are presented. The analysis showed that the observed intensity of muon bundles at primary cosmic ray energies of about 1 EeV and higher can be compatible with the expectation in frame of widely used hadron interaction models only under the assumption of an extremely heavy mass composition. This conclusion is consistent with data of several experiments on investigations of muon content in air showers, but contradicts the available fluorescence data on $X_{\text{max}}$ which favor a light mass composition at these energies. In order to clarify the nature of the "muon puzzle", investigations of the muon bundle energy deposit in the detector material were carried out. For the first time, experimental estimates of the average energy of muons in the bundles of inclined air showers initiated by primary particles with energies from 10 to 1000 PeV have been obtained.
Cosmic ray interactions in the atmosphere: QGSJET-III and other models

Sergey Ostapchenko

SciPost Phys. Proc. 13, 004 (2023) · published 28 September 2023 | · pdf

The physics content of the QGSJET-III Monte Carlo generator of high energy hadronic collisions is discussed. New theoretical approaches implemented in QGSJET-III are addressed in some detail and a comparison to alternative treatments of other cosmic ray interaction models is performed. Calculated characteristics of cosmic ray-induced extensive air showers are presented and differences between the respective results of QGSJET-III and other models are analyzed. In particular, it is demonstrated that those differences are partly caused by severe deficiencies of the other interaction models.
Recent results from the TOTEM collaboration and the discovery of the odderon

Christophe Royon

SciPost Phys. Proc. 13, 005 (2023) · published 28 September 2023 | · pdf

We describe the most recent results from the TOTEM collaboration on elastic, inelastic and total cross sections as well as the odderon discovery by the D0 and TOTEM collaborations.
New determination of the production cross section for secondary positrons and electrons in the Galaxy

Luca Orusa, Mattia Di Mauro, Fiorenza Donato, Michael Korsmeier

SciPost Phys. Proc. 13, 006 (2023) · published 28 September 2023 | · pdf

The cosmic-ray fluxes of electrons and positrons ($e^{±}$) are measured with high precision by the space-borne particle spectrometer AMS-02. To infer a precise interpretation of the production processes for $e^{±}$ in our Galaxy, it is necessary to have an accurate description of the secondary component, produced by the interaction of cosmic-ray proton and helium with the interstellar medium atoms. We determine new analytical functions of the Lorentz invariant cross section for the production of $e^±$ by fitting data from collider experiments. The total differential cross section $d\sigma/dT_{e^±}(p+p→ e^±+X)$ is predicted with an uncertainty of about 5-7% in the energies relevant for AMS-02 positron flux. For further information about this work refer to [Phys. Rev. D 105, 123021 (2022)].
Overview of quarkonium production with ALICE at the LHC

Hushnud Hushnud on behalf of the ALICE collaboration

SciPost Phys. Proc. 13, 007 (2023) · published 28 September 2023 | · pdf

ALICE is a general purpose experiment designed to investigate nucleus-nucleus collisions at the Large Hadron Collider (LHC), located at CERN. The ALICE detector is optimized for the reconstruction of quarkonia through the dimuon decay channel at foward rapidity as well as the dielectron decay channel at midrapidity. In this contribution, quarkonium measurements performed by the ALICE collaboration at both midrapidity and forward rapidity for various energies and colliding systems (pp, p-Pb and Pb-Pb), will be discussed and compared to theory.
The ALPACA experiment: The project of the first sub-PeV gamma-ray observation in the southern sky

Teruyoshi Kawashima for the ALPACA Collaboration

SciPost Phys. Proc. 13, 008 (2023) · published 28 September 2023 | · pdf

The ALPACA experiment is a project aiming to observe sub-PeV gamma rays for the first time in the southern hemisphere. The main goal of ALPACA is to identify PeVatrons, the accelerators of Galactic PeV cosmic rays, by observing sub-PeV pion-decay gamma rays generated in interactions between PeV cosmic rays and the interstellar medium. This new air shower experiment is located at an altitude of 4,740 m above sea level in the middle of Mt. Chacaltaya in Bolivia. The air shower array consists of 401 scintillation counters covering an 83,000 m$^2$ surface area. In addition, a water-Cherenkov-type muon detector array with an area of 3,700 m$^2$ is installed to discriminate gamma rays from background cosmic rays. The prototype array ALPAQUITA will start data taking in 2022 and will extend to ALPACA in 2024. We report on a general introduction to ALPACA, the progress of the project, and the sensitivity to sub-PeV gamma rays.
Point sources of ultra-high-energy neutrinos: Minimalist predictions for near-future discovery

Damiano F. G. Fiorillo, Mauricio Bustamante, Victor B. Valera

SciPost Phys. Proc. 13, 009 (2023) · published 28 September 2023 | · pdf

The discovery of ultra-high-energy neutrinos, with energies above 100 PeV, may soon be within reach of upcoming neutrino telescopes. We present a robust framework to compute the statistical significance of point-source discovery via the detection of neutrino multiplets. We apply it to the radio array component of IceCube-Gen2. To identify a source with $3\sigma$ significance, IceCube-Gen2 will need to detect a triplet, at best, and an octuplet, at worst, depending on whether the source is steady-state or transient, and on its position in the sky. The discovery, or absence, of sources significantly constrains the properties of the source population.
Neutrinos from near and far: Results from the IceCube Neutrino Observatory

Tianlu Yuan for the IceCube Collaboration

SciPost Phys. Proc. 13, 010 (2023) · published 28 September 2023 | · pdf

Instrumenting a gigaton of ice at the geographic South Pole, the IceCube Neutrino Observatory has been at the forefront of groundbreaking scientific discoveries over the past decade. These include the observation of a flux of TeV-PeV astrophysical neutrinos, detection of the first astrophysical neutrino on the Glashow resonance and evidence of the blazar TXS 0506+056 as the first known astronomical source of high-energy neutrinos. Several questions, however, remain, pertaining to the precise origins of astrophysical neutrinos, their production mechanisms at the source and in Earth’s atmosphere and in the context of physics beyond the Standard Model. This proceeding highlights some of our latest results, from new constraints on neutrino interactions and oscillations to the latest measurements of the astrophysical neutrino flux and searches for their origins to future prospects with IceCube-Gen2.
The Tunka-Grande scintillation array: Current results

A. L. Ivanova, I. Astapov, P. Bezyazeekov, E. Bonvech, A. Borodin, N. Budnev, A. Bulan, D. Chernov, A. Chiavassa, A. Dyachok, A. Gafarov, A. Garmash, V. Grebenyuk, E. Gress, O. Gress, T. Gress, A. Grinyuk, O. Grishin, A. D. Ivanova, N. Kalmykov, V. Kindin, S. Kiryuhin, R. Kokoulin, K. Kompaniets, E. Korosteleva, V. Kozhin, E. Kravchenko, A. Kryukov, L. Kuzmichev, A. Lagutin, M. Lavrova, Y. Lemeshev, B. Lubsandorzhiev, N. Lubsandorzhiev, A. Lukanov, D. Lukyantsev, S. Malakhov, R. Mirgazov, R. Monkhoev, E. Osipova, A. Pakhorukov, L. Pankov, A. Pan, A. Panov, A. Petrukhin, I. Poddubnyi, D. Podgrudkov, V. Poleschuk, V. Ponomareva, E. Popova, E. Postnikov, V. Prosin, V. Ptuskin, A. Pushnin, R. Raikin, A. Razumov, G. Rubtsov, E. Ryabov, Y. Sagan, V. Samoliga, A. Satyshev, A. Silaev, A. Silaev, A. Sidorenkov, A. Skurikhin, A. Sokolov, L. Sveshnikova, V. Tabolenko, L. Tkachev, A. Tanaev, M. Ternovoy, R. Togoo, N. Ushakov, A. Vaidyanathan, P. Volchugov, N. Volkov, D. Voronin, A. Zagorodnikov, D. Zhurov, I. Yashin

SciPost Phys. Proc. 13, 011 (2023) · published 28 September 2023 | · pdf

The Tunka-Grande experiment is a scintillation array with about 0.5 km$^2$ sensitive area at Tunka Valley, Siberia, for measuring charged particles and muons in extensive air showers (EASs). Tunka-Grande is optimized for cosmic ray studies in the energy range 10 PeV to about 1 EeV, where exploring the composition is of fundamental importance for understanding the transition from galactic to extragalactic origin of cosmic rays. This paper attempts to provide a synopsis of the current results of the experiment. In particular, the reconstruction of the all-particle energy spectrum in the range of 10 PeV to 1 EeV based on experimental data from four observation seasons is presented.
Results on high energy galactic cosmic rays from the DAMPE space mission

Leandro Silveri on behalf of the DAMPE Collaboration

SciPost Phys. Proc. 13, 012 (2023) · published 28 September 2023 | · pdf

DAMPE (Dark Matter Particle Explorer) is a satellite-born experiment launched in 2015 in a sun-synchronous orbit at 500 km altitude, and it has been taking data in stable conditions ever since. Its main goals include the spectral measurements up to very high energies, cosmic electrons/positrons and gamma rays up to tens of TeV, and protons and nuclei up to hundreds of TeV. The detector's main features include the 32 radiation lengths deep calorimeter and large geometric acceptance, making DAMPE one of the most powerful space instruments in operation, covering with high statistics and small systematics the high energy frontier up to several hundreds TeV. The results of spectral measurements of different species are shown and discussed.
Limits to gauge coupling in the dark sector of super-heavy dark matter particles from the Pierre Auger Observatory data

Olivier Deligny for the Pierre Auger Collaboration

SciPost Phys. Proc. 13, 013 (2023) · published 28 September 2023 | · pdf

Assuming that the energy density of super-heavy particles matches that of dark matter observed today, tight constraints on the couplings governing the decay process are presented as a function of the particle mass. These constraints are obtained from the lack of signatures that would be suggestive of decaying super-heavy $X$ particles in the data of the Pierre Auger Observatory. In particular, instanton-induced decay processes allow us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: $\alpha_X \lesssim 0.09$, for $10^{9} \lesssim M_X/\mathrm{GeV} < 10^{19}$. Cosmological aspects for super-heavy dark matter production during the reheating epoch are discussed.
The composition of cosmic rays according to the data on EAS cores

S. B. Shaulov, V. A. Ryabov, S. E. Pyatovsky, A. L. Shepetov, V. V. Zhukov

SciPost Phys. Proc. 13, 014 (2023) · published 28 September 2023 | · pdf

The main purpose of this work is to find the causes of the break of the cosmic ray spectrum at an energy of 3 PeV, which is called the knee. The solution of the problem is associated with the determination of the nuclear composition of cosmic rays in the knee area. The conclusions of this work are based on the analysis of the characteristics of the EAS cores obtained using X-ray emulsion chambers. According to these data, a number of anomalous effects are observed in the knee region, such as scaling violation in the spectra of secondary hadrons, an excess of muons in EAS with gamma families and others. At the same energies equivalent to 1-100 PeV the laboratory system colliders show scaling behavior. So analysis of the data on the EAS cores suggests that the knee in their spectrum is formed by a component of cosmic rays of a non-nuclear nature, possibly consisting of stable (quasi-stable) particles of hypothetical strange quark matter, which named strangelets. This is the only model of the knee compatible with the magnetic rigidity of the nuclear spectra break R=100 TV. In fact, stranglets are stable heavy quasi-nuclei with a positive electric charge of Z=30-1000, so the mechanism of their acceleration coincides with the nuclear one. The break of the cosmic ray spectrum can be associated with a significantly larger mass of strangelets compared to nuclei.
A measurement of the proton plus helium spectrum of cosmic rays in the TeV region with HAWC

Juan Carlos Arteaga-Velázquez on behalf of the HAWC collaboration

SciPost Phys. Proc. 13, 015 (2023) · published 28 September 2023 | · pdf

HAWC is an air-shower detector designed to study TeV gamma and cosmic rays. The observatory is composed of a 22000 $m^2$ array of 300 water Cherenkov tanks (4.5 m deep x 7.3 m diameter) with 4 photomultipliers (PMT) each. The instrument registers the number of hit PMTs, the timing information and the total charge at the PMTs during the event. From these data, shower observables such as the arrival direction, the core position at ground, the lateral age and the primary energy are estimated. In this work, we study the distribution of the shower age vs the primary energy of a sample of shower data collected by HAWC from June 2015 to June 2019 and employ a shower-age cut based on predictions of QGSJET-II-04 to separate a subsample of events dominated by H and He primaries. Using these data and a dedicated analysis, we reconstruct the cosmic ray spectrum of H+He from 6 to 158 TeV, which shows the presence of a softening at around 24 TeV with a statistical significance of 4.1$\sigma$.
Recent results from LHCb for astroparticle physics

Hans Dembinski on behalf of the LHCb collaboration

SciPost Phys. Proc. 13, 016 (2023) · published 28 September 2023 | · pdf

The LHCb experiment is a general-purpose forward spectrometer designed for the study of heavy flavour physics at the LHC. The acceptance in the pseudorapidity range $2 < \eta < 5$ with full tracking and particle identification capabilities down to very small transverse momentum make LHCb also ideal to study hadron production in the forward region. Measuring and modelling these processes is essential for the simulation of interactions of high-energy cosmic rays with matter, like Earth's atmosphere or the interstellar medium. We present recently published analyses from the LHCb collaboration relevant for this application.
Measuring the attenuation length of muon number in the air shower with muon detectors of 3/4 LHAASO array

Xiaoting Feng, Hengying Zhang, Cunfeng Feng, Lingling Ma on behalf of the LHAASO Collaboration

SciPost Phys. Proc. 13, 017 (2023) · published 28 September 2023 | · pdf

LHAASO KM2A consists of 5915 scintillation detectors and 1188 muon detectors, and the muon detectors cover 4% area of the whole array with 30 m interdetector spacing. The muon number in air shower events, with very high energy, is investigated with the data recorded by muon detector of the 3/4 LHAASO array in 2021. The attenuation length of muon number in the air shower is measured by fitting the muon number with constant flux in various zenith angles, based on the constant intensity cut method. The variation of the attenuation length as shower energy from hundreds TeV to tens PeV is presented. The results of simulation also is presented for comparing.
Uncertainty in mean $X_{\rm max}$ from diffractive dissociation estimated using measurements of accelerator experiments

Ken Ohashi, Hiroaki Menjo, Takashi Sako, Yoshitaka Itow

SciPost Phys. Proc. 13, 018 (2023) · published 28 September 2023 | · pdf

Mass composition is important for understanding the origin of ultra-high-energy cosmic rays. However, interpretation of mass composition from air shower experiments is challenging, owing to significant uncertainty in hadronic interaction models adopted in air shower simulation. A particular source of uncertainty is diffractive dissociation, as its measurements in accelerator experiments demonstrated significant systematic uncertainty. In this research, we estimate the uncertainty in $\langle X_{\rm max}\rangle$ from the uncertainty of the measurement of diffractive dissociation by the ALICE experiment. The maximum uncertainty size of the entire air shower was estimated to be $^{+4.0}_{-5.6} \mathrm{g/cm^2}$ for air showers induced by $10^{17}$ eV proton, which is not negligible in the uncertainty of $\langle X_{\rm max}\rangle$ predictions.
The full coverage approach to the detection of Extensive Air Showers

Giuseppe Di Sciascio

SciPost Phys. Proc. 13, 019 (2023) · published 28 September 2023 | · pdf

A shower array exploiting the full coverage approach with a high segmentation of the readout allow to image the front of atmospheric showers with unprecedented resolution and detail. The grid distance determines the energy threshold (small energy showers are lost in the gap between detectors) and the quality of the shower sampling. Therefore, this experimental solution is needed to detect showers with a threshold in the 100 GeV range. The full coverage approach has been exploited in the ARGO-YBJ experiment. In this contribution we will summarise the advantages of this technique and discuss possible applications in new wide field of view detectors.
On irregularities in the cosmic ray spectrum of $10^{16}-10^{18}$ eV range

Stanislav P. Knurenko, Igor S. Petrov

SciPost Phys. Proc. 13, 020 (2023) · published 28 September 2023 | · pdf

Existing small, medium and large arrays for the study of cosmic rays of ultra-high energies are aimed for obtaining information about our galaxy and extragalactic space, namely to search and study astronomical objects that produce the flux of relativistic particles. The drift and interaction of such particles with magnetic fields and shock waves taking place in interstellar space causes the same interest. The shape of the energy spectrum of cosmic rays in the energy range $10^{15}-10^{18}$ eV, where the "knee" and the "second knee" are observed, can be formed as a superposition of the partial spectra of various chemical elements. Verification of galactic models, using recent experimental spectral data, makes it possible to study the nature of the galactic and extragalactic components of cosmic rays. The paper presents the result of the energy spectrum of cosmic rays in the range $10^{16}-10^{18}$ eV of measurements obtained with the Small Cherenkov array - a part of the Yakutsk array.
Highlights of the results from the GRAPES-3 experiment

Hariharan Balakrishnan, S. Ahmad, M. Chakraborty, S.R. Dugad, U.D. Goswami, S.K. Gupta, Y. Hayashi, P. Jagadeesan, A. Jain, P. Jain, S. Kawakami, H. Kojima, S. Mahapatra, P.K. Mohanty, R. Moharana, Y. Muraki, P.K. Nayak, T. Nonaka, A. Oshima, D. Pattanaik, B.P. Pant, M. Rameez, K. Ramesh, L.V. Reddy, S. Shibata, F. Varsi, M. Zuberi

SciPost Phys. Proc. 13, 021 (2023) · published 28 September 2023 | · pdf

The GRAPES-3 experiment is a unique, extensive air shower experiment consisting of 400 scintillator detectors spread over 25000 m$^2$ and a 560 m$^2$ muon telescope. The experiment located at Ooty, India, has been collecting data for the past two decades. The unique capabilities of GRAPES-3 have allowed the study of cosmic rays over energies from a few TeV to tens of PeV and beyond. The measurement of the directional flux of muons (E$_\mu$≥1 GeV) by the large muon telescope permits an excellent gamma-hadron separation, which then becomes a powerful tool in the study of multi-TeV gamma-ray sources and the composition of primary cosmic rays. However, the high precision measurements also enable studies of transient atmospheric and interplanetary phenomena such as those produced by thunderstorms and geomagnetic storms. This paper presents some exciting new and recent results, including updates on various ongoing analyses.
ALICE at the LHC and astrophysics: From providing input for the search for antinuclei in space to constraining the equation of state of neutron stars

Alexander Kalweit on behalf of the ALICE collaboration

SciPost Phys. Proc. 13, 022 (2023) · published 29 September 2023 | · pdf

The ALICE experiment at the LHC was originally designed to study the creation of the quark-gluon-plasma in heavy-ion collisions, a new state of matter in which quarks and gluons are not confined into hadrons. More recently, the versatility of both the Large Hadron Collider and the ALICE apparatus have given additionally access to a unique set of nuclear and hadronic physics measurements. The main results from this new and dynamic research area will be presented. The application of these findings to astrophysical challenges, ranging from the equation of state of neutron stars to the search for dark matter in space, will be discussed.
DEASA studies and applications to space physics and muon tomography

Sonali Bhatnagar

SciPost Phys. Proc. 13, 023 (2023) · published 29 September 2023 | · pdf

The high energy cosmic rays entering the Earth’s atmosphere throw light upon many aspects of Astroparticle and Particle Physics. This work outlines investigative learning about these high energy primaries based on a mini array DEASA in Agra, India. DEASA (Dayalbagh Educational Air Shower Array) consists of eight plastic scintillators each with an area of 1 square meter. This array covers an area of 260 square meters and is the first array in the northern part of our country. A real-life application of these highly energetic particles has been to find the best material to protect the astronaut from them in form of galactic cosmic rays (GCR). Geant4 based hadronic binary model was used in simulation of phantom, vehicle, SEP (Solar Energetic Particles) and GCR shield. The SEP shielding material was fixed as water and GCR shield was varied among aluminum, Polystyrene and Polyethylene. The poly materials were found to be the best due to large amount of hydrogen (H) and low atomic number (Z). In this work the equivalent dose deposited in the phantom with Polystyrene material for GCR shield was calculated to be minimum (107 sievert) as compared to the other materials. In the second application, the high energy muons have been studied to image nuclear caskets through muon tomography. In this Monte Carlo based simulation, a dry cask container containing different number of the UO2 rods have been bombarded with definite energy muons to measure the muon scattering . The parameters computed in this work are energy loss, radiation length and scattering angle which can calibrate these containers for correct identification of nuclear wastage.
India based neutrino observatory, physics reach and status report

D. Indumathi

SciPost Phys. Proc. 13, 024 (2023) · published 29 September 2023 | · pdf

The India-based Neutrino Observatory (INO) is a proposed underground facility located in India that will primarily house the magnetised Iron CALorimeter (ICAL) detector to study atmospheric neutrinos produced by interactions of cosmic rays with Earth's atmosphere. The physics goal is to to make precision measurements of the neutrino mixing and oscillation parameters through such a study. We present here the results from detailed simulations studies, as well as a status report on the project. In particular, we highlight the sensitivity of ICAL to the open issue of the neutrino mass ordering, which can be determined independent of the CP phase at ICAL.
Mass testing of SiPMs for the CMVD at IICHEP

Mamta Jangra, Raj Bhupen, Gobinda Majumder, Kiran Gothe, Mandar Saraf, Nandkishor Parmar, Bheesette Satyanarayana, Ravindra R. Shinde, Shobha K. Rao, Suresh S. Upadhya, Vivek M. Datar, Douglas A. Glenzinski, Alan Bross, Anna Pla-Dalmau, Vishnu V. Zutshi, Robert Craig Group, Edmond Craig Dukes

SciPost Phys. Proc. 13, 025 (2023) · published 29 September 2023 | · pdf

A Cosmic Muon Veto Detector (CMVD) is being built around the mini-Iron Calorimeter (mini-ICAL) detector at the transit campus of the India based Neutrino Observatory, Madurai. The CMV detector will be made using extruded plastic scintillators with embedded wavelength shifting (WLS) fibres which propagate re-emitted photons of longer wavelengths to silicon photo-multipliers (SiPMs). The SiPMs detect these scintillation photons, producing electronic signals. The design goal for the cosmic muon veto efficiency of the CMV is $>$99.99% and fake veto rate less than 10$^{-5}$. A testing system was developed, using an LED driver, to measure the noise rate and gain of each SiPM, and thus determine its overvoltage ($V_{ov}$). This paper describes the test results and the analysed characteristics of about 3.5k SiPMs.
Probing hadronic interaction models with the hybrid data of the Pierre Auger Observatory

Jakub Vícha for the Pierre Auger Collaboration

SciPost Phys. Proc. 13, 026 (2023) · published 29 September 2023 | · pdf

Presently large systematic uncertainties remain in the description of hadronic interactions at ultra-high energies and a fully consistent description of air-shower experimental data is yet to be reached. The amount of data collected by the Pierre Auger Observatory using simultaneously the fluorescence and surface detectors in the energy range 10$^{18.5}$ -10$^{19.0}$ eV has provided opportunity to perform a multi-parameter test of model predictions. We apply a global method to simultaneously fit the mass composition of cosmic rays and adjustments to the simulated depth of shower maximum, and hadronic signal at ground level. The best description of the hybrid data is obtained for a deeper scale of simulated depth of shower maximum than predicted by hadronic interaction models tuned to the LHC data. Consequently, the deficit of the simulated hadronic signal at ground level, dominated by muons, is alleviated with respect to the unmodified hadronic interaction models. Because of the size of the adjustments to simulated depth of shower maximum and hadronic signal and the large number of events in the sample, the statistical significance of these assumed adjustments is large, greater than 5$\sigma_{stat}$, even for the combination of the systematic experimental shifts within 1$\sigma_{sys}$ that are the most favorable for the models.
TAIGA - An advanced hybrid detector complex for astroparticle physics and high energy gamma-ray astronomy

N. M. Budnev, I. Astapov, P. Bezyazeekov, E. Bonvech, A. Borodin, A. Bulan, D. Chernov, A. Chiavassa, A. Dyachok, A. Gafarov, A. Garmash, V. Grebenyuk, E. Gress, O. Gress, T. Gress, A. Grinyuk, O. Grishin, A. D. Ivanova, A. L. Ivanova, N. Kalmykov, V. Kindin, S. Kiryuhin, R. Kokoulin, K. Kompaniets, E. Korosteleva, V. Kozhin, E. Kravchenko, A. Kryukov, L. Kuzmichev, A. Lagutin, M. Lavrova, Y. Lemeshev, B. Lubsandorzhiev, N. Lubsandorzhiev, A. Lukanov, D. Lukyantsev, S. Malakhov, R. Mirgazov, R. Monkhoev, E. Osipova, A. Pakhorukov, L. Pankov, A. Pan, A. Panov, A. Petrukhin, I. Poddubnyi, D. Podgrudkov, V. Ponomareva, E. Popova, E. Postnikov, V. Prosin, V. Ptuskin, A. Pushnin, R. Raikin, A. Razumov, G. Rubtsov, E. Ryabov, V. Samoliga, A. Satyshev, A. Silaev, A. Silaev, A. Sidorenkov, A. Skurikhin, A. Sokolov, L. Sveshnikova, V. Tabolenko, L. Tkachev, A. Tanaev, M. Ternovoy, R. Togoo, N. Ushakov, A. Vaidyanathan, P. Volchugov, N. Volkov, D. Voronin, A. Zagorodnikov, D. Zhurov, I. Yashin

SciPost Phys. Proc. 13, 027 (2023) · published 29 September 2023 | · pdf

The physical motivations, present status, main results in study of cosmic rays and in the field of gamma-ray astronomy as well future plans of the TAIGA-1 (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) project are presented. The TAIGA observatory addresses ground-based gamma-ray astronomy and astroparticle physics at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. The pilot TAIGA-1 complex is located in the Tunka valley, 50 km west from the southern tip of the lake Baikal.
CORSIKA 8 - the next-generation air shower simulation framework

Tim Huege for the CORSIKA 8 Collaboration

SciPost Phys. Proc. 13, 028 (2023) · published 29 September 2023 | · pdf

For more than 20 years, the community has heavily relied on CORSIKA for the simulation of extensive air showers, their Cherenkov light emission and their radio signals. While tremendously successful, the Fortran-based monolithic design of CORSIKA up to version 7 limits adaptation to new experimental needs, for example, in complex scenarios where showers transition from air into dense media, and to new computing paradigms such as the use of multi-core and GPU parallelization. With CORSIKA 8, we have reimplemented the core functionality of CORSIKA in a modern, modular, C++-based simulation framework, and successfully validated it against CORSIKA 7. Here, we discuss the philosophy of CORSIKA 8, showcase some example applications, and present the current state of implementation as well as the plans for the future.
A contribution of the HAWC observatory to the TeV era in the high energy gamma-ray astrophysics: The case of the TeV-halos

Ramiro Torres-Escobedo, Hao Zhou, Eduardo de la Fuente for the HAWC Collaboration

SciPost Phys. Proc. 13, 029 (2023) · published 29 September 2023 | · pdf

We present a short overview of the TeV-Halos objects as a discovery and a relevant contribution of the High Altitude Water Çerenkov (HAWC) observatory to TeV astrophysics. We discuss history, discovery, knowledge, and the next step through a new and more detailed analysis than the original study in 2017. TeV-Halos will contribute to resolving the problem of the local positron excess observed on the Earth. To clarify the latter, understanding the diffusion process is mandatory.
The KM3NeT infrastructure: Status and first results

Annarita Margiotta on behalf of the KM3NeT Collaboration

SciPost Phys. Proc. 13, 030 (2023) · published 29 September 2023 | · pdf

KM3NeT is a research infrastructure in construction under the Mediterranean Sea. It hosts two large volume neutrino Cherenkov telescopes: ARCA at a depth of 3500 m, located offshore Sicily, and ORCA, 2500 m under the sea level, offshore the southern French coast. The two detectors share the same detection principle and technology and the same data acquisition design, the only difference being the geometrical arrangement of the optical sensors. This allows to span a wide range of neutrino energy and cover a large scientific program: The study of neutrino properties, first of all neutrino mass ordering, the identification and study of high energy neutrino astrophysical sources, indirect dark matter searches and core collapse supernovae detection.
Updated results on the cosmic ray energy spectrum and composition from the GRAPES-3 experiment

F. Varsi, S. Ahmad, M. Chakraborty, A. Chandra, S. R. Dugad, U. D. Goswami, S. K. Gupta, B. Hariharan, Y. Hayashi, P. Jagadeesan, A. Jain , P. Jain, S. Kawakami, H. Kojima, S. Mahapatra, P. K. Mohanty, R. Moharana, Y. Muraki, P. K. Nayak, T. Nonaka, A. Oshima, B. P. Pant, D. Pattanaik, G. Pradhan, M. Rameez, K. Ramesh, L. V. Reddy, R. Sahoo, R. Scaria, S. Shibata, K. Tanaka, M. Zuberi

SciPost Phys. Proc. 13, 031 (2023) · published 29 September 2023 | · pdf

Here, we present the updated results on the cosmic ray energy spectrum and composition analysis from the GRAPES-3 experiment over the energy range of 50 TeV to 1000 TeV since ICRC 2021. The simulation of cosmic ray showers was performed using the post-LHC high energy hadronic interaction model QGSJetII-04 and low energy hadronic model FLUKA. A detailed GEANT4 simulation of the GRAPES-3 muon telescope was performed. The composition was obtained by fitting simulated muon multiplicity distributions for proton, helium, nitrogen, aluminium, and iron primaries to the observed data. The energy spectrum connects to the direct measurements with a fairly good agreement in flux.
Muons in showers with energy $\boldsymbol{E_{0} \geq}$ 5 EeV and QGSjetII-04 and EPOS LHC models of hadronic interactions. Is there a muon deficit in the models?

Stanislav Knurenko, Igor Petrov

SciPost Phys. Proc. 13, 032 (2023) · published 29 September 2023 | · pdf

The paper presents data on the muon component with a threshold $\varepsilon_{thr} ≥$ 1 GeV. Air showers were registered at the Yakutsk array during almost 50 years of continuous air shower observations. The characteristics of muons are compared with calculations of QGSjetII-04 and EPOS LHC models for a proton and an iron nucleus. There is a muon deficit in the models, at energies greater than 5 EeV. To make an agreement between experimental data and simulations on muons, further tuning of the models is required.
Update on the angular resolution of GRAPES-3 experiment based on Moon shadow analysis

D. Pattanaik, S. Ahmad, M. Chakraborty, S. R. Dugad, U. D. Goswami, S. K. Gupta, B. Hariharan, Y. Hayashi, P. Jagadeesan, A. Jain, P. Jain, S. Kawakami, H. Kojima, S. Mahapatra, P. K. Mohanty, R. Moharana, Y. Muraki, P. K. Nayak, T. Nonaka, A. Oshima, B. P. Pant, M. Rameez, K. Ramesh, L. V. Reddy, S. Shibata, F. Varsi, M. Zuberi

SciPost Phys. Proc. 13, 033 (2023) · published 29 September 2023 | · pdf

GRAPES-3 is an extensive air shower array located at Ooty (11.6$^\circ$N, 76.7$^\circ$E, 2200 m a.s.l.) in southern India. Recently, the angular resolution of the GRAPES-3 array has been improved by correcting the shower front curvature based on the shower size and age. Here, we present the results of the angular resolution and pointing accuracy of the array through observation of the Moon shadow. We have analyzed the data for the period of 2014-2016 containing $\sim$ 3$×$10$^9$ air shower events with a median energy of 15 TeV. A significant improvement in the angular resolution has been observed compared to the earlier analysis by the group through the Moon shadow method and is comparable to the arrays located at a 2 km higher altitude than the GRAPES-3 experiment.
Astroparticle and particle physics at ultra-high energy: Results from the Pierre Auger Observatory

Antonella Castellina for the Pierre Auger Collaboration

SciPost Phys. Proc. 13, 034 (2023) · published 29 September 2023 | · pdf

The scientific achievements of the Pierre Auger Collaboration cover diverse and complementary fields of research. The search for the origin of ultra-high energy cosmic rays (UHECRs) is based on the measurement of the energy spectrum and mass composition of the primaries, on studies of multi-messengers, and on extensive anisotropy searches. With the collected data it is also possible to explore the characteristics of hadronic interactions at energies unreachable at human-made accelerators, and to assess the existence of non-standard physics effects. A selection of the latest results is presented and the emerging picture is discussed.
VERITAS highlights of observations and results

Sonal R. Patel for the VERITAS collaboration

SciPost Phys. Proc. 13, 035 (2023) · published 29 September 2023 | · pdf

Located in southern Arizona, VERITAS is amongst the most sensitive detectors for astrophysical very high energy (VHE; E>100 GeV) gamma rays and has been operational since April 2007. We highlight some recent results from VERITAS observations. These include the long-term observations of the gamma-ray binaries HESS J0632+057 and LS I +61° 303, the observations of the Galactic Center region, and of the supernova remnant Cas A. We discuss the results from a decade of multi-wavelength observations of the blazar 1ES 1215+303, the EHT 2017 campaign on the M87 galaxy, the discovery of 3C 264 in VHE, and the observation of three flaring quasars. Brief highlights of the indirect dark matter searches and targets-of-opportunity (ToO) observations are also discussed. The ToO observations allow for rapid follow-up of multi-messenger alerts and astrophysical transients.
Results from recent analysis of KASCADE-Grande data

Donghwa Kang, J. C. Arteaga-Velázquez, M. Bertaina, A. Chiavassa, K. Daumiller, V. de Souza, R. Engel, A. Gherghel-Lascu, C. Grupen, A. Haungs, J. R. Hörandel, T. Huege, K. -H. Kampert, K. Link, H. J. Mathes, S. Ostapchenko, T. Pierog, D. Rivera-Rangel, M. Roth, H. Schieler, F. G. Schröder, O. Sima, A. Weindl, J. Wochele, J. Zabierowski

SciPost Phys. Proc. 13, 036 (2023) · published 29 September 2023 | · pdf

KASCADE and its extension array of KASCADE-Grande were devoted to measure individual air showers of cosmic rays in the primary energy range of 100 TeV to 1 EeV. The experiment has substantially contributed to investigate the energy spectrum and mass composition of cosmic rays in the transition region from galactic to extragalactic origin of cosmic rays as well as to quantify the characteristics of hadronic interaction models in the air shower development through validity tests using the multi-detector information from KASCADE-Grande. Although the data accumulation was completed in 2013, data analysis is still continuing. Recently, we investigated the reliability of the new hadronic interactions models of the SIBYLL version 2.3d only with the energy spectra from the KASCADE-Grande data. The evolution of the muon content of high energy air showers in the atmosphere is studied as well, using EPOS-LHC, SIBYLL 2.3, QGSJET-II-04 and SIBYLL 2.3c. In this talk, recent results from KASCADE-Grande and the update of the KASCADE Cosmic Ray Data Centre (KCDC) will be discussed.
Primary cosmic ray energy spectrum and mean mass composition using data from the TAIGA astrophysical complex

V. Prosin, I. Astapov, P. Bezyazeekov, E. Bonvech, A. Borodin, A. Bulan, A. Chiavassa, D. Chernov, A. Dyachok, A. Gafarov, A. Garmash, V. Grebenyuk, O. Gress, E. Gress, T. Gress, A. Grinyuk, O. Grishin, A. D. Ivanova, A. L. Ivanova, N. Kalmykov, V. Kindin, S. Kiryuhin, R. Kokoulin, K. Kompaniets, E. Korosteleva, V. Kozhin, E. Kravchenko, A. Kryukov, L. Kuzmichev, A. Lagutin, M. Lavrova, Y. Lemeshev, B. Lubsandorzhiev, N. Lubsandorzhiev, A. Lukanov, D. Lukyantsev, S. Malakhov, R. Mirgazov, R. Monkhoev, E. Okuneva, E. Osipova, A. Pakhorukov, A. Pan, L. Panasenko, L. Pankov, A. D. Panov, A. Petrukhin, I. Poddubny, D. Podgrudkov, V. Poleschuk, V. Ponomareva, E. Popova, E. Postnikov, V. Ptuskin, A. Pushnin, R. Raikin, A. Razumov, G. Rubtsov, E. Ryabov, Y. Sagan, V. Samoliga, A. Silaev, A. Silaev, A. Sidorenkov, A. Skurikhin, A. Sokolov, L. Sveshnikova, V. Tabolenko, A. Tanaev, B. Tarashchansky, M. Y. Ternovoy, L. Tkachev, R. Togoo, N. Ushakov, A. Vaidyanathan, P. Volchugov, N. Volkov, D. Voronin, A. Zagorodnikov, A. Zhaglova, D. Zhurov, I. Yashin

SciPost Phys. Proc. 13, 037 (2023) · published 29 September 2023 | · pdf

The corrected dependence of the mean depth of the EAS maximum $X_{max}$ on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 years. The parameter $\langle\ln A\rangle$, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of $2\cdot 10^{14}$ – $2\cdot 10^{16}$ eV was reconstructed using the new parameter $Q_{100}$ the Cherenkov light flux at the core distance 100 m. Change of the parameter for the energy reconstuction for the TAIGA-HiSCORE from $Q_{200}$ to $Q_{100}$ provides a decreasing energy threshold for the spectrum to about 200 TeV.
EUSO-SPB2: A sub-orbital cosmic ray and neutrino multi-messenger pathfinder observatory

Austin Cummings, Johannes Eser, George Filippatos, Angela V. Olinto, Tonia M. Venters, Lawrence Wiencke for the JEM-EUSO collaboration

SciPost Phys. Proc. 13, 038 (2023) · published 29 September 2023 | · pdf

The next generation of ultra-high energy cosmic ray (UHECR) and very-high energy neutrino observatories will address the challenge of the extremely low fluxes of these particles at the highest energies. EUSO-SPB2 (Extreme Universe Space Observatory on a Super Pressure Balloon 2) is designed to prepare space missions to address this challenge. EUSO-SPB2 is equipped with 2 telescopes: the Fluorescence Telescope, which will point downwards and measure fluorescence emission from UHECR air showers with an energy above 2 EeV, and the Cherenkov Telescope (CT), which will point towards the Earth's limb and measure direct Cherenkov emission from cosmic rays with energies above 1 PeV verifying the technique. Pointed below the limb, the CT will search for Cherenkov emission produced by neutrino-sourced tau-lepton decays above 10 PeV energies and study backgrounds for such events. The EUSO-SPB2 mission will provide pioneering observations and technical milestones on the path towards a space-based multi-messenger observatory.
The all-particle energy spectrum of cosmic rays from 10 TeV to 1 PeV measured with HAWC

Jorge A. Morales-Soto, Juan C. Arteaga-Velázquez on behalf of the HAWC Collaboration

SciPost Phys. Proc. 13, 039 (2023) · published 29 September 2023 | · pdf

The HAWC observatory is an air-shower detector, which is designed to study both astrophysical gamma-rays in the TeV region and galactic cosmic rays in the energy interval from 1 TeV to 1 PeV. This energy regime is interesting for cosmic ray research, since indirect observations overlap with direct measurements, which offers the opportunity for cross calibration and studies of experimental systematic errors in both techniques. One quantity that could help for this purpose is the all-particle energy spectrum of cosmic rays. In this work, we present an update of HAWC measurements on the total cosmic-ray energy spectrum between 10 TeV and 1 PeV. The spectrum was obtained from an unfolding analysis of almost two years of HAWC's data, which was collected from January, 2018 to December, 2019. For the energy estimation, we employed the high-energy hadronic interaction model QGSJET-II-04. As in a previous work of HAWC, published in 2017, we observed the presence of a knee-like feature in the region of tens of TeV.
Direct measurements of cosmic rays with the calorimetric electron telescope on the international space station

Y. Akaike, O. Adriani, K. Asano, Y. Asaoka, E. Berti, G. Bigongiari, W. R. Binns, M. Bongi, P. Brogi, A. Bruno, J. H. Buckley, N. Cannady, G. Castellini, C. Checchia, M. L. Cherry, G. Collazuol, K. Ebisawa, A. W. Ficklin, H. Fuke, S. Gonzi, T. G. Guzik, T. Hams, K. Hibino, M. Ichimura, K. Ioka, W. Ishizaki, M. H. Israel, K. Kasahara, J. Kataoka, R. Kataoka, Y. Katayose, C. Kato, N. Kawanaka, Y. Kawakubo, K. Kobayashi, K. Kohri, H. S. Krawczynski, J. F. Krizmanic, P. Maestro, P. S. Marrocchesi, A. M. Messineo, J. W. Mitchell, S. Miyake, A. A. Moiseev, M. Mori, N. Mori, H. M. Motz, K. Munakata, S. Nakahira, J. Nishimura, G. A. de Nolfo, S. Okuno, J. F. Ormes, S. Ozawa, L. Pacini, P. Papini, B. F. Rauch, S. B. Ricciarini, K. Sakai, T. Sakamoto, M. Sasaki, Y. Shimizu, A. Shiomi, P. Spillantini, F. Stolzi, S. Sugita, A. Sulaj, M. Takita, T. Tamura, T. Terasawa, S. Torii, Y. Tsunesada, Y. Uchihori, E. Vannuccini, J. P. Wefel, K. Yamaoka, S. Yanagita, A. Yoshida, K. Yoshida, W. V. Zober

SciPost Phys. Proc. 13, 040 (2023) · published 29 September 2023 | · pdf

The CALorimetric Electron Telescope, CALET, has been measuring high-energy cosmic rays on the International Space Station since October 13, 2015. The scientific objectives addressed by the mission are to search for possible nearby sources of high-energy electrons and potential signatures of dark matter, and to investigate the details of galactic cosmic-ray acceleration and propagation. The calorimetric instrument, which is 30 radiation lengths or 1.3 proton interaction lengths thick with fine imaging capability, is optimized to measure cosmic-ray electrons by achieving large proton rejection and excellent energy resolution well into the TeV region. In addition, very wide dynamic range of energy measurement and individual charge identification capability enable us to measure proton and nuclei spectra from a few tens GeV to a PeV scale. Nearly 20 million cosmic-ray shower events over 10 GeV per month are triggered and the continuous observation has been kept without any major interruption since the start of operation. Using the data obtained over 6.5 years of operation, we will present a brief summary of the CALET observation including electron spectrum, and proton and nuclei spectra as well as the performance study on orbit with MC simulations.
Highlights from the Telescope Array Experiment

Hiroyuki Sagawa for the Telescope Array Collaboration

SciPost Phys. Proc. 13, 041 (2023) · published 29 September 2023 | · pdf

The Telescope Array (TA) is the largest hybrid cosmic ray detector in the Northern Hemisphere, which observes primary particles in the energy range from 2 PeV to 100 EeV. The main TA detector consists of 507 plastic scintillation counters on a 1.2-km spacing square grid and fluorescence detectors at three stations overlooking the sky above the surface detector array. The TA Low energy Extension (TALE) detector, which consists of ten fluorescence telescopes, and 80 infill surface detectors with 400m and 600 m spacing, has continued to provide stable observations since its construction completion in 2018. The TAx4, a plan to quadruple the detection area of TA is also ongoing. About half of the planned surface detectors have been deployed, and the current TAx4 continues to operate stably as a hybrid detector. I review the present status of the TA experiment and the recent results on the cosmic-ray anisotropy, mass composition and energy spectrum.
Looking forward to forward physics at the CERN's LHC

Luis A. Anchordoqui

SciPost Phys. Proc. 13, 042 (2023) · published 19 October 2023 | · pdf

For decades, new physics searches in collider experiments have focused on the high-$p_T$ region. However, it has recently become evident that the LHC physics potential has not been fully exploited. To be specific, forward collisions, which produce particles along the beamline with enormous rates, have been almost completely ignored. For all practical purposes, these collisions are a treasure trove of physics, containing the highest-energy neutrinos ever produced by humans, as well as possible evidence for dark matter, light and weakly-coupled particles, and new forces. In the upcoming LHC Run 3 the ForwArd Search ExpeRiment (FASER) and its cousin FASER$\nu$ will extend the LHC's physics potential. A continuation of this forward physics program for the HL-LHC aims at the Forward Physics Facility (FPF), with larger scale experiments. In this report, I give an overview of the physics motivations for FASER, FASER$\nu$, and the FPF experiments, including both Standard Model and beyond Standard Model physics.