TY - JOUR
T1 - Follow-up Analysis to Geminga’s Contribution to the Local Positron Excess with the HAWC gamma-ray Observatory
AU - HAWC Collaboration
AU - Torres-Escobedo, Ramiro
AU - Zhou, Hao
AU - de la Fuente, Eduardo
AU - Di Mauro, Mattia
AU - Abeysekara, A. U.
AU - Albert, A.
AU - Alfaro, R.
AU - Alvarez, C.
AU - Álvarez, J. D.
AU - Angeles Camacho, J. R.
AU - Arteaga-Velázquez, J. C.
AU - Arunbabu, K. P.
AU - Avila Rojas, D.
AU - Ayala Solares, H. A.
AU - Babu, R.
AU - Baghmanyan, V.
AU - Barber, A. S.
AU - Becerra Gonzalez, J.
AU - Belmont-Moreno, E.
AU - BenZvi, S. Y.
AU - Berley, D.
AU - Brisbois, C.
AU - Caballero-Mora, K. S.
AU - Capistrán, T.
AU - Carramiñana, A.
AU - Casanova, S.
AU - Chaparro-Amaro, O.
AU - Cotti, U.
AU - Cotzomi, J.
AU - Coutiño de León, S.
AU - De la Fuente, E.
AU - de León, C.
AU - Diaz-Cruz, L.
AU - Diaz Hernandez, R.
AU - Díaz-Vélez, J. C.
AU - Dingus, B. L.
AU - Durocher, M.
AU - DuVernois, M. A.
AU - Ellsworth, R. W.
AU - Engel, K.
AU - Espinoza, C.
AU - Fan, K. L.
AU - Fang, K.
AU - Fernández Alonso, M.
AU - Fick, B.
AU - Fleischhack, H.
AU - Flores, J. L.
AU - Fraija, N. I.
AU - Garcia, D.
AU - Mostafá, M.
N1 - Funding Information:
We acknowledge the support from: the US National Science Foundation (NSF); the US Department of Energy Office of High-Energy Physics; the Laboratory Directed Research and Development (LDRD) program of Los Alamos National Laboratory; Consejo Nacional de Ciencia y Tecnología (CONACyT), México, grants 271051, 232656, 260378, 179588, 254964, 258865, 243290, 132197, A1-S-46288, A1-S-22784, cátedras 873, 1563, 341, 323, Red HAWC, México; DGAPA-UNAM grants IG101320, IN111716-3, IN111419, IA102019, IN110621, IN110521; VIEP-BUAP; PIFI 2012, 2013, PROFOCIE 2014, 2015; the University of Wisconsin Alumni Research Foundation; the Institute of Geophysics, Planetary Physics, and Signatures at Los Alamos National Laboratory; Polish Science Centre grant, DEC-2017/27/B/ST9/02272; Coordinación de la Investigación Científica de la Universidad Michoacana; Royal Society - Newton Advanced Fellowship 180385; General-itat Valenciana, grant CIDEGENT/2018/034; Chulalongkorn University’s CUniverse (CUAASC) grant; Coordinación General Académica e Innovación (CGAI-UdeG), PRODEP-SEP UDG-CA-499; Institute of Cosmic Ray Research (ICRR), University of Tokyo. H.F. acknowledges support by NASA under award number 80GSFC21M0002. We also acknowledge the significant contributions over many years of Stefan Westerhoff, Gaurang Yodh and Arnulfo Zepeda Dominguez, all deceased members of the HAWC collaboration. Thanks to Scott Delay, Luciano Díaz and Eduardo Murrieta for technical support.
Publisher Copyright:
© Copyright owned by the author(s).
PY - 2022/3/18
Y1 - 2022/3/18
N2 - Two cosmic-ray experiments, PAMELA and AMS-02, measured an abnormal positron excess above 10 GeV. This excess is well understood, but it has been considered direct evidence of dark matter. However, this excess could be produced by nearby pulsars too. The HAWC collaboration previously studied the extended gamma-ray emission of two nearby pulsars, Geminga and PSR B0656+14, but found no significant contribution to this excess from these pulsars. The previous study of HAWC led to the reinterpretation of our result and initiated the concept of inverse Compton (IC) halos. Fitting a new halo model and 1343 days of data from the HAWC gamma-ray observatory may better constrain the contribution of these pulsars to the positron excess. This halo model utilizes 3D templates of gamma-ray emission from electron IC interactions to fit the diffusion coefficient and electron injection spectral index. This model can further help to study the energy-dependent diffusion and incorporate anisotropic diffusion with the proper motion of the pulsar.
AB - Two cosmic-ray experiments, PAMELA and AMS-02, measured an abnormal positron excess above 10 GeV. This excess is well understood, but it has been considered direct evidence of dark matter. However, this excess could be produced by nearby pulsars too. The HAWC collaboration previously studied the extended gamma-ray emission of two nearby pulsars, Geminga and PSR B0656+14, but found no significant contribution to this excess from these pulsars. The previous study of HAWC led to the reinterpretation of our result and initiated the concept of inverse Compton (IC) halos. Fitting a new halo model and 1343 days of data from the HAWC gamma-ray observatory may better constrain the contribution of these pulsars to the positron excess. This halo model utilizes 3D templates of gamma-ray emission from electron IC interactions to fit the diffusion coefficient and electron injection spectral index. This model can further help to study the energy-dependent diffusion and incorporate anisotropic diffusion with the proper motion of the pulsar.
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M3 - Conference article
AN - SCOPUS:85145009073
SN - 1824-8039
VL - 395
JO - Proceedings of Science
JF - Proceedings of Science
M1 - 842
T2 - 37th International Cosmic Ray Conference, ICRC 2021
Y2 - 12 July 2021 through 23 July 2021
ER -