Depth of Ultra High Energy Cosmic Ray Induced Air Shower Maxima Measured by the Telescope Array Black Rock and Long Ridge FADC Fluorescence Detectors and Surface Array in Hybrid Mode

R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, R. Azuma, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, A. Di Matteo, T. Fujii, K. Fujita, M. Fukushima, G. Furlich, T. Goto, W. Hanlon & 120 others M. Hayashi, Y. Hayashi, N. Hayashida, K. Hibino, K. Honda, D. Ikeda, N. Inoue, T. Ishii, R. Ishimori, H. Ito, D. Ivanov, H. M. Jeong, S. M. Jeong, C. C.H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, S. Kishigami, S. Kitamura, Y. Kitamura, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, K. Martens, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, K. Nagasawa, S. Nagataki, R. Nakamura, T. Nakamura, T. Nonaka, H. Oda, S. Ogio, J. Ogura, M. Ohnishi, H. Ohoka, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, Shunsuke Ozawa, I. H. Park, M. S. Pshirkov, D. C. Rodriguez, G. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, K. Saito, Y. Saito, N. Sakaki, N. Sakurai, L. M. Scott, T. Seki, K. Sekino, P. D. Shah, F. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, J. D. Smith, P. Sokolsky, B. T. Stokes, S. R. Stratton, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, Y. Tsunesada, K. Tsutsumi, Y. Uchihori, S. Udo, F. Urban, T. Wong, M. Yamamoto, R. Yamane, H. Yamaoka, K. Yamazaki, J. Yang, K. Yashiro, Y. Yoneda, S. Yoshida, H. Yoshii, Y. Zhezher, Z. Zundel

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

The Telescope Array (TA) observatory utilizes fluorescence detectors and surface detectors (SDs) to observe air showers produced by ultra high energy cosmic rays in Earth's atmosphere. Cosmic-ray events observed in this way are termed hybrid data. The depth of air shower maximum is related to the mass of the primary particle that generates the shower. This paper reports on shower maxima data collected over 8.5 yr using the Black Rock Mesa and Long Ridge fluorescence detectors in conjunction with the array of SDs. We compare the means and standard deviations of the observed Xmax distributions with Monte Carlo Xmax distributions of unmixed protons, helium, nitrogen, and iron, all generated using the QGSJet II-04 hadronic model. We also perform an unbinned maximum likelihood test of the observed data, which is subjected to variable systematic shifting of the data Xmax distributions to allow us to test the full distributions, and compare them to the Monte Carlo to see which elements are not compatible with the observed data. For all energy bins, QGSJet II-04 protons are found to be compatible with TA hybrid data at the 95% confidence level after some systematic Xmax shifting of the data. Three other QGSJet II-04 elements are found to be compatible using the same test procedure in an energy range limited to the highest energies where data statistics are sparse.

Original languageEnglish
Article number76
JournalAstrophysical Journal
Volume858
Issue number2
DOIs
Publication statusPublished - 2018 May 10

Fingerprint

cosmic ray showers
cosmic ray
ridges
cosmic rays
fluorescence
telescopes
rocks
detectors
air
showers
rock
energy
protons
Earth atmosphere
mesas
confidence
standard deviation
observatories
helium
statistics

Keywords

  • acceleration of particles
  • astrochemistry
  • astroparticle physics
  • cosmic rays
  • elementary particles

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Depth of Ultra High Energy Cosmic Ray Induced Air Shower Maxima Measured by the Telescope Array Black Rock and Long Ridge FADC Fluorescence Detectors and Surface Array in Hybrid Mode. / Abbasi, R. U.; Abe, M.; Abu-Zayyad, T.; Allen, M.; Azuma, R.; Barcikowski, E.; Belz, J. W.; Bergman, D. R.; Blake, S. A.; Cady, R.; Cheon, B. G.; Chiba, J.; Chikawa, M.; Di Matteo, A.; Fujii, T.; Fujita, K.; Fukushima, M.; Furlich, G.; Goto, T.; Hanlon, W.; Hayashi, M.; Hayashi, Y.; Hayashida, N.; Hibino, K.; Honda, K.; Ikeda, D.; Inoue, N.; Ishii, T.; Ishimori, R.; Ito, H.; Ivanov, D.; Jeong, H. M.; Jeong, S. M.; Jui, C. C.H.; Kadota, K.; Kakimoto, F.; Kalashev, O.; Kasahara, K.; Kawai, H.; Kawakami, S.; Kawana, S.; Kawata, K.; Kido, E.; Kim, H. B.; Kim, J. H.; Kim, J. H.; Kishigami, S.; Kitamura, S.; Kitamura, Y.; Kuzmin, V.; Kuznetsov, M.; Kwon, Y. J.; Lee, K. H.; Lubsandorzhiev, B.; Lundquist, J. P.; Machida, K.; Martens, K.; Matsuyama, T.; Matthews, J. N.; Mayta, R.; Minamino, M.; Mukai, K.; Myers, I.; Nagasawa, K.; Nagataki, S.; Nakamura, R.; Nakamura, T.; Nonaka, T.; Oda, H.; Ogio, S.; Ogura, J.; Ohnishi, M.; Ohoka, H.; Okuda, T.; Omura, Y.; Ono, M.; Onogi, R.; Oshima, A.; Ozawa, Shunsuke; Park, I. H.; Pshirkov, M. S.; Rodriguez, D. C.; Rubtsov, G.; Ryu, D.; Sagawa, H.; Sahara, R.; Saito, K.; Saito, Y.; Sakaki, N.; Sakurai, N.; Scott, L. M.; Seki, T.; Sekino, K.; Shah, P. D.; Shibata, F.; Shibata, T.; Shimodaira, H.; Shin, B. K.; Shin, H. S.; Smith, J. D.; Sokolsky, P.; Stokes, B. T.; Stratton, S. R.; Stroman, T. A.; Suzawa, T.; Takagi, Y.; Takahashi, Y.; Takamura, M.; Takeda, M.; Takeishi, R.; Taketa, A.; Takita, M.; Tameda, Y.; Tanaka, H.; Tanaka, K.; Tanaka, M.; Thomas, S. B.; Thomson, G. B.; Tinyakov, P.; Tkachev, I.; Tokuno, H.; Tomida, T.; Troitsky, S.; Tsunesada, Y.; Tsutsumi, K.; Uchihori, Y.; Udo, S.; Urban, F.; Wong, T.; Yamamoto, M.; Yamane, R.; Yamaoka, H.; Yamazaki, K.; Yang, J.; Yashiro, K.; Yoneda, Y.; Yoshida, S.; Yoshii, H.; Zhezher, Y.; Zundel, Z.

In: Astrophysical Journal, Vol. 858, No. 2, 76, 10.05.2018.

Research output: Contribution to journalArticle

Abbasi, RU, Abe, M, Abu-Zayyad, T, Allen, M, Azuma, R, Barcikowski, E, Belz, JW, Bergman, DR, Blake, SA, Cady, R, Cheon, BG, Chiba, J, Chikawa, M, Di Matteo, A, Fujii, T, Fujita, K, Fukushima, M, Furlich, G, Goto, T, Hanlon, W, Hayashi, M, Hayashi, Y, Hayashida, N, Hibino, K, Honda, K, Ikeda, D, Inoue, N, Ishii, T, Ishimori, R, Ito, H, Ivanov, D, Jeong, HM, Jeong, SM, Jui, CCH, Kadota, K, Kakimoto, F, Kalashev, O, Kasahara, K, Kawai, H, Kawakami, S, Kawana, S, Kawata, K, Kido, E, Kim, HB, Kim, JH, Kim, JH, Kishigami, S, Kitamura, S, Kitamura, Y, Kuzmin, V, Kuznetsov, M, Kwon, YJ, Lee, KH, Lubsandorzhiev, B, Lundquist, JP, Machida, K, Martens, K, Matsuyama, T, Matthews, JN, Mayta, R, Minamino, M, Mukai, K, Myers, I, Nagasawa, K, Nagataki, S, Nakamura, R, Nakamura, T, Nonaka, T, Oda, H, Ogio, S, Ogura, J, Ohnishi, M, Ohoka, H, Okuda, T, Omura, Y, Ono, M, Onogi, R, Oshima, A, Ozawa, S, Park, IH, Pshirkov, MS, Rodriguez, DC, Rubtsov, G, Ryu, D, Sagawa, H, Sahara, R, Saito, K, Saito, Y, Sakaki, N, Sakurai, N, Scott, LM, Seki, T, Sekino, K, Shah, PD, Shibata, F, Shibata, T, Shimodaira, H, Shin, BK, Shin, HS, Smith, JD, Sokolsky, P, Stokes, BT, Stratton, SR, Stroman, TA, Suzawa, T, Takagi, Y, Takahashi, Y, Takamura, M, Takeda, M, Takeishi, R, Taketa, A, Takita, M, Tameda, Y, Tanaka, H, Tanaka, K, Tanaka, M, Thomas, SB, Thomson, GB, Tinyakov, P, Tkachev, I, Tokuno, H, Tomida, T, Troitsky, S, Tsunesada, Y, Tsutsumi, K, Uchihori, Y, Udo, S, Urban, F, Wong, T, Yamamoto, M, Yamane, R, Yamaoka, H, Yamazaki, K, Yang, J, Yashiro, K, Yoneda, Y, Yoshida, S, Yoshii, H, Zhezher, Y & Zundel, Z 2018, 'Depth of Ultra High Energy Cosmic Ray Induced Air Shower Maxima Measured by the Telescope Array Black Rock and Long Ridge FADC Fluorescence Detectors and Surface Array in Hybrid Mode', Astrophysical Journal, vol. 858, no. 2, 76. https://doi.org/10.3847/1538-4357/aabad7
Abbasi, R. U. ; Abe, M. ; Abu-Zayyad, T. ; Allen, M. ; Azuma, R. ; Barcikowski, E. ; Belz, J. W. ; Bergman, D. R. ; Blake, S. A. ; Cady, R. ; Cheon, B. G. ; Chiba, J. ; Chikawa, M. ; Di Matteo, A. ; Fujii, T. ; Fujita, K. ; Fukushima, M. ; Furlich, G. ; Goto, T. ; Hanlon, W. ; Hayashi, M. ; Hayashi, Y. ; Hayashida, N. ; Hibino, K. ; Honda, K. ; Ikeda, D. ; Inoue, N. ; Ishii, T. ; Ishimori, R. ; Ito, H. ; Ivanov, D. ; Jeong, H. M. ; Jeong, S. M. ; Jui, C. C.H. ; Kadota, K. ; Kakimoto, F. ; Kalashev, O. ; Kasahara, K. ; Kawai, H. ; Kawakami, S. ; Kawana, S. ; Kawata, K. ; Kido, E. ; Kim, H. B. ; Kim, J. H. ; Kim, J. H. ; Kishigami, S. ; Kitamura, S. ; Kitamura, Y. ; Kuzmin, V. ; Kuznetsov, M. ; Kwon, Y. J. ; Lee, K. H. ; Lubsandorzhiev, B. ; Lundquist, J. P. ; Machida, K. ; Martens, K. ; Matsuyama, T. ; Matthews, J. N. ; Mayta, R. ; Minamino, M. ; Mukai, K. ; Myers, I. ; Nagasawa, K. ; Nagataki, S. ; Nakamura, R. ; Nakamura, T. ; Nonaka, T. ; Oda, H. ; Ogio, S. ; Ogura, J. ; Ohnishi, M. ; Ohoka, H. ; Okuda, T. ; Omura, Y. ; Ono, M. ; Onogi, R. ; Oshima, A. ; Ozawa, Shunsuke ; Park, I. H. ; Pshirkov, M. S. ; Rodriguez, D. C. ; Rubtsov, G. ; Ryu, D. ; Sagawa, H. ; Sahara, R. ; Saito, K. ; Saito, Y. ; Sakaki, N. ; Sakurai, N. ; Scott, L. M. ; Seki, T. ; Sekino, K. ; Shah, P. D. ; Shibata, F. ; Shibata, T. ; Shimodaira, H. ; Shin, B. K. ; Shin, H. S. ; Smith, J. D. ; Sokolsky, P. ; Stokes, B. T. ; Stratton, S. R. ; Stroman, T. A. ; Suzawa, T. ; Takagi, Y. ; Takahashi, Y. ; Takamura, M. ; Takeda, M. ; Takeishi, R. ; Taketa, A. ; Takita, M. ; Tameda, Y. ; Tanaka, H. ; Tanaka, K. ; Tanaka, M. ; Thomas, S. B. ; Thomson, G. B. ; Tinyakov, P. ; Tkachev, I. ; Tokuno, H. ; Tomida, T. ; Troitsky, S. ; Tsunesada, Y. ; Tsutsumi, K. ; Uchihori, Y. ; Udo, S. ; Urban, F. ; Wong, T. ; Yamamoto, M. ; Yamane, R. ; Yamaoka, H. ; Yamazaki, K. ; Yang, J. ; Yashiro, K. ; Yoneda, Y. ; Yoshida, S. ; Yoshii, H. ; Zhezher, Y. ; Zundel, Z. / Depth of Ultra High Energy Cosmic Ray Induced Air Shower Maxima Measured by the Telescope Array Black Rock and Long Ridge FADC Fluorescence Detectors and Surface Array in Hybrid Mode. In: Astrophysical Journal. 2018 ; Vol. 858, No. 2.
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title = "Depth of Ultra High Energy Cosmic Ray Induced Air Shower Maxima Measured by the Telescope Array Black Rock and Long Ridge FADC Fluorescence Detectors and Surface Array in Hybrid Mode",
abstract = "The Telescope Array (TA) observatory utilizes fluorescence detectors and surface detectors (SDs) to observe air showers produced by ultra high energy cosmic rays in Earth's atmosphere. Cosmic-ray events observed in this way are termed hybrid data. The depth of air shower maximum is related to the mass of the primary particle that generates the shower. This paper reports on shower maxima data collected over 8.5 yr using the Black Rock Mesa and Long Ridge fluorescence detectors in conjunction with the array of SDs. We compare the means and standard deviations of the observed Xmax distributions with Monte Carlo Xmax distributions of unmixed protons, helium, nitrogen, and iron, all generated using the QGSJet II-04 hadronic model. We also perform an unbinned maximum likelihood test of the observed data, which is subjected to variable systematic shifting of the data Xmax distributions to allow us to test the full distributions, and compare them to the Monte Carlo to see which elements are not compatible with the observed data. For all energy bins, QGSJet II-04 protons are found to be compatible with TA hybrid data at the 95{\%} confidence level after some systematic Xmax shifting of the data. Three other QGSJet II-04 elements are found to be compatible using the same test procedure in an energy range limited to the highest energies where data statistics are sparse.",
keywords = "acceleration of particles, astrochemistry, astroparticle physics, cosmic rays, elementary particles",
author = "Abbasi, {R. U.} and M. Abe and T. Abu-Zayyad and M. Allen and R. Azuma and E. Barcikowski and Belz, {J. W.} and Bergman, {D. R.} and Blake, {S. A.} and R. Cady and Cheon, {B. G.} and J. Chiba and M. Chikawa and {Di Matteo}, A. and T. Fujii and K. Fujita and M. Fukushima and G. Furlich and T. Goto and W. Hanlon and M. Hayashi and Y. Hayashi and N. Hayashida and K. Hibino and K. Honda and D. Ikeda and N. Inoue and T. Ishii and R. Ishimori and H. Ito and D. Ivanov and Jeong, {H. M.} and Jeong, {S. M.} and Jui, {C. C.H.} and K. Kadota and F. Kakimoto and O. Kalashev and K. Kasahara and H. Kawai and S. Kawakami and S. Kawana and K. Kawata and E. Kido and Kim, {H. B.} and Kim, {J. H.} and Kim, {J. H.} and S. Kishigami and S. Kitamura and Y. Kitamura and V. Kuzmin and M. Kuznetsov and Kwon, {Y. J.} and Lee, {K. H.} and B. Lubsandorzhiev and Lundquist, {J. P.} and K. Machida and K. Martens and T. Matsuyama and Matthews, {J. N.} and R. Mayta and M. Minamino and K. Mukai and I. Myers and K. Nagasawa and S. Nagataki and R. Nakamura and T. Nakamura and T. Nonaka and H. Oda and S. Ogio and J. Ogura and M. Ohnishi and H. Ohoka and T. Okuda and Y. Omura and M. Ono and R. Onogi and A. Oshima and Shunsuke Ozawa and Park, {I. H.} and Pshirkov, {M. S.} and Rodriguez, {D. C.} and G. Rubtsov and D. Ryu and H. Sagawa and R. Sahara and K. Saito and Y. Saito and N. Sakaki and N. Sakurai and Scott, {L. M.} and T. Seki and K. Sekino and Shah, {P. D.} and F. Shibata and T. Shibata and H. Shimodaira and Shin, {B. K.} and Shin, {H. S.} and Smith, {J. D.} and P. Sokolsky and Stokes, {B. T.} and Stratton, {S. R.} and Stroman, {T. A.} and T. Suzawa and Y. Takagi and Y. Takahashi and M. Takamura and M. Takeda and R. Takeishi and A. Taketa and M. Takita and Y. Tameda and H. Tanaka and K. Tanaka and M. Tanaka and Thomas, {S. B.} and Thomson, {G. B.} and P. Tinyakov and I. Tkachev and H. Tokuno and T. Tomida and S. Troitsky and Y. Tsunesada and K. Tsutsumi and Y. Uchihori and S. Udo and F. Urban and T. Wong and M. Yamamoto and R. Yamane and H. Yamaoka and K. Yamazaki and J. Yang and K. Yashiro and Y. Yoneda and S. Yoshida and H. Yoshii and Y. Zhezher and Z. Zundel",
year = "2018",
month = "5",
day = "10",
doi = "10.3847/1538-4357/aabad7",
language = "English",
volume = "858",
journal = "Astrophysical Journal",
issn = "0004-637X",
publisher = "IOP Publishing Ltd.",
number = "2",

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TY - JOUR

T1 - Depth of Ultra High Energy Cosmic Ray Induced Air Shower Maxima Measured by the Telescope Array Black Rock and Long Ridge FADC Fluorescence Detectors and Surface Array in Hybrid Mode

AU - Abbasi, R. U.

AU - Abe, M.

AU - Abu-Zayyad, T.

AU - Allen, M.

AU - Azuma, R.

AU - Barcikowski, E.

AU - Belz, J. W.

AU - Bergman, D. R.

AU - Blake, S. A.

AU - Cady, R.

AU - Cheon, B. G.

AU - Chiba, J.

AU - Chikawa, M.

AU - Di Matteo, A.

AU - Fujii, T.

AU - Fujita, K.

AU - Fukushima, M.

AU - Furlich, G.

AU - Goto, T.

AU - Hanlon, W.

AU - Hayashi, M.

AU - Hayashi, Y.

AU - Hayashida, N.

AU - Hibino, K.

AU - Honda, K.

AU - Ikeda, D.

AU - Inoue, N.

AU - Ishii, T.

AU - Ishimori, R.

AU - Ito, H.

AU - Ivanov, D.

AU - Jeong, H. M.

AU - Jeong, S. M.

AU - Jui, C. C.H.

AU - Kadota, K.

AU - Kakimoto, F.

AU - Kalashev, O.

AU - Kasahara, K.

AU - Kawai, H.

AU - Kawakami, S.

AU - Kawana, S.

AU - Kawata, K.

AU - Kido, E.

AU - Kim, H. B.

AU - Kim, J. H.

AU - Kim, J. H.

AU - Kishigami, S.

AU - Kitamura, S.

AU - Kitamura, Y.

AU - Kuzmin, V.

AU - Kuznetsov, M.

AU - Kwon, Y. J.

AU - Lee, K. H.

AU - Lubsandorzhiev, B.

AU - Lundquist, J. P.

AU - Machida, K.

AU - Martens, K.

AU - Matsuyama, T.

AU - Matthews, J. N.

AU - Mayta, R.

AU - Minamino, M.

AU - Mukai, K.

AU - Myers, I.

AU - Nagasawa, K.

AU - Nagataki, S.

AU - Nakamura, R.

AU - Nakamura, T.

AU - Nonaka, T.

AU - Oda, H.

AU - Ogio, S.

AU - Ogura, J.

AU - Ohnishi, M.

AU - Ohoka, H.

AU - Okuda, T.

AU - Omura, Y.

AU - Ono, M.

AU - Onogi, R.

AU - Oshima, A.

AU - Ozawa, Shunsuke

AU - Park, I. H.

AU - Pshirkov, M. S.

AU - Rodriguez, D. C.

AU - Rubtsov, G.

AU - Ryu, D.

AU - Sagawa, H.

AU - Sahara, R.

AU - Saito, K.

AU - Saito, Y.

AU - Sakaki, N.

AU - Sakurai, N.

AU - Scott, L. M.

AU - Seki, T.

AU - Sekino, K.

AU - Shah, P. D.

AU - Shibata, F.

AU - Shibata, T.

AU - Shimodaira, H.

AU - Shin, B. K.

AU - Shin, H. S.

AU - Smith, J. D.

AU - Sokolsky, P.

AU - Stokes, B. T.

AU - Stratton, S. R.

AU - Stroman, T. A.

AU - Suzawa, T.

AU - Takagi, Y.

AU - Takahashi, Y.

AU - Takamura, M.

AU - Takeda, M.

AU - Takeishi, R.

AU - Taketa, A.

AU - Takita, M.

AU - Tameda, Y.

AU - Tanaka, H.

AU - Tanaka, K.

AU - Tanaka, M.

AU - Thomas, S. B.

AU - Thomson, G. B.

AU - Tinyakov, P.

AU - Tkachev, I.

AU - Tokuno, H.

AU - Tomida, T.

AU - Troitsky, S.

AU - Tsunesada, Y.

AU - Tsutsumi, K.

AU - Uchihori, Y.

AU - Udo, S.

AU - Urban, F.

AU - Wong, T.

AU - Yamamoto, M.

AU - Yamane, R.

AU - Yamaoka, H.

AU - Yamazaki, K.

AU - Yang, J.

AU - Yashiro, K.

AU - Yoneda, Y.

AU - Yoshida, S.

AU - Yoshii, H.

AU - Zhezher, Y.

AU - Zundel, Z.

PY - 2018/5/10

Y1 - 2018/5/10

N2 - The Telescope Array (TA) observatory utilizes fluorescence detectors and surface detectors (SDs) to observe air showers produced by ultra high energy cosmic rays in Earth's atmosphere. Cosmic-ray events observed in this way are termed hybrid data. The depth of air shower maximum is related to the mass of the primary particle that generates the shower. This paper reports on shower maxima data collected over 8.5 yr using the Black Rock Mesa and Long Ridge fluorescence detectors in conjunction with the array of SDs. We compare the means and standard deviations of the observed Xmax distributions with Monte Carlo Xmax distributions of unmixed protons, helium, nitrogen, and iron, all generated using the QGSJet II-04 hadronic model. We also perform an unbinned maximum likelihood test of the observed data, which is subjected to variable systematic shifting of the data Xmax distributions to allow us to test the full distributions, and compare them to the Monte Carlo to see which elements are not compatible with the observed data. For all energy bins, QGSJet II-04 protons are found to be compatible with TA hybrid data at the 95% confidence level after some systematic Xmax shifting of the data. Three other QGSJet II-04 elements are found to be compatible using the same test procedure in an energy range limited to the highest energies where data statistics are sparse.

AB - The Telescope Array (TA) observatory utilizes fluorescence detectors and surface detectors (SDs) to observe air showers produced by ultra high energy cosmic rays in Earth's atmosphere. Cosmic-ray events observed in this way are termed hybrid data. The depth of air shower maximum is related to the mass of the primary particle that generates the shower. This paper reports on shower maxima data collected over 8.5 yr using the Black Rock Mesa and Long Ridge fluorescence detectors in conjunction with the array of SDs. We compare the means and standard deviations of the observed Xmax distributions with Monte Carlo Xmax distributions of unmixed protons, helium, nitrogen, and iron, all generated using the QGSJet II-04 hadronic model. We also perform an unbinned maximum likelihood test of the observed data, which is subjected to variable systematic shifting of the data Xmax distributions to allow us to test the full distributions, and compare them to the Monte Carlo to see which elements are not compatible with the observed data. For all energy bins, QGSJet II-04 protons are found to be compatible with TA hybrid data at the 95% confidence level after some systematic Xmax shifting of the data. Three other QGSJet II-04 elements are found to be compatible using the same test procedure in an energy range limited to the highest energies where data statistics are sparse.

KW - acceleration of particles

KW - astrochemistry

KW - astroparticle physics

KW - cosmic rays

KW - elementary particles

UR - http://www.scopus.com/inward/record.url?scp=85047180615&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85047180615&partnerID=8YFLogxK

U2 - 10.3847/1538-4357/aabad7

DO - 10.3847/1538-4357/aabad7

M3 - Article

VL - 858

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 2

M1 - 76

ER -