Investigating the uniformity of the excess gamma rays towards the galactic center region

被引：23

作者：

Horiuchi, Shunsaku ^{[1
]}

Kaplinghat, Manoj ^{[2
]}

Kwa, Anna ^{[2
]}

机构：

[1] Virginia Tech, Dept Phys, Ctr Neutrino Phys, Blacksburg, VA 24061 USA

[2] Univ Calif Irvine, Ctr Cosmol, Dept Phys & Astron, Irvine, CA 92697 USA

来源：

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS | 2016年 / 11期

关键词：

gamma ray experiments; dark matter experiments; millisecond pulsars; FERMI-LAT OBSERVATIONS; ANNIHILATING DARK-MATTER; MILLISECOND PULSARS; GLOBULAR-CLUSTERS; EMISSION; POPULATION; BUBBLES; DISCOVERY; ORIGIN; SIGNAL;

D O I：

10.1088/1475-7516/2016/11/053

中图分类号：

P1 [天文学];

学科分类号：

0704 ;

摘要：

We perform a composite likelihood analysis of subdivided regions within the central 26 degrees x20 degrees of the MilkyWay, with the aim of characterizing the spectrum of the gamma-ray galactic center excess in regions of varying galactocentric distance. Outside of the innermost few degrees, we fi nd that the radial pro fi le of the excess is background-model dependent and poorly constrained. The spectrum of the excess emission is observed to extend upwards of 10 GeV outside similar to 5 degrees ffi in radius, but cuts o ff steeply between 10-20 GeV only in the innermost few degrees. If interpreted as a real feature of the excess, this radial variation in the spectrum has important implications for both astrophysical and dark matter interpretations of the galactic center excess. Single-component dark matter annihilation models face challenges in reproducing this variation; on the other hand, a population of unresolved millisecond pulsars contributing both prompt and secondary inverse Compton emission may be able to explain the spectrum as well as its spatial dependency. We show that the expected di ff erences in the photon-count distributions of a smooth dark matter annihilation signal and an unresolved point source population are an order of magnitude smaller than the fluctuations in residuals after fi tting the data, which implies that mismodeling is an important systematic e ff ect in point source analyses aimed at resolving the gamma-ray excess.

引用

页数：29

共 65 条

[1] Discovery of a new galactic center excess consistent with upscattered starlight [J].

Abazajian, Kevork N. ;

Canac, Nicolas ;

Horiuchi, Shunsaku ;

Kaplinghat, Manoj ;

Kwa, Anna .

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, 2015, (07)

[2] Astrophysical and dark matter interpretations of extended gamma-ray emission from the Galactic Center [J].

Abazajian, Kevork N. ;

Canac, Nicolas ;

Horiuchi, Shunsaku ;

Kaplinghat, Manoj .

PHYSICAL REVIEW D, 2014, 90 (02)

[3] Detection of a gamma-ray source in the Galactic Center consistent with extended emission from dark matter annihilation and concentrated astrophysical emission [J].

Abazajian, Kevork N. ;

Kaplinghat, Manoj .

PHYSICAL REVIEW D, 2012, 86 (08)

[4] The consistency of Fermi-LAT observations of the galactic center with a millisecond pulsar population in the central stellar cluster [J].

Abazajian, Kevork N. .

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, 2011, (03)

[5] FERMI LARGE AREA TELESCOPE THIRD SOURCE CATALOG [J].

Acero, F. ;

Ackermann, M. ;

Ajello, M. ;

Albert, A. ;

Atwood, W. B. ;

Axelsson, M. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Bastieri, D. ;

Belfiore, A. ;

Bellazzini, R. ;

Bissaldi, E. ;

Blandford, R. D. ;

Bloom, E. D. ;

Bogart, J. R. ;

Bonino, R. ;

Bottacini, E. ;

Bregeon, J. ;

Britto, R. J. ;

Bruel, P. ;

Buehler, R. ;

Burnett, T. H. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caputo, R. ;

Caragiulo, M. ;

Caraveo, P. A. ;

Casandjian, J. M. ;

Cavazzuti, E. ;

Charles, E. ;

Chaves, R. C. G. ;

Chekhtman, A. ;

Cheung, C. C. ;

Chiang, J. ;

Chiaro, G. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Cominsky, L. R. ;

Conrad, J. ;

Cutini, S. ;

D'Ammando, F. ;

de Angelis, A. ;

DeKlotz, M. ;

de Palma, F. ;

Desiante, R. ;

Digel, S. W. ;

Di Venere, L. .

ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 2015, 218 (02)

[6] THE SPECTRUM OF ISOTROPIC DIFFUSE GAMMA-RAY EMISSION BETWEEN 100 MeV AND 820 GeV [J].

Ackermann, M. ;

Ajello, M. ;

Albert, A. ;

Atwood, W. B. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Bastieri, D. ;

Bechtol, K. ;

Bellazzini, R. ;

Bissaldi, E. ;

Blandford, R. D. ;

Bloom, E. D. ;

Bottacini, E. ;

Brandt, T. J. ;

Bregeon, J. ;

Bruel, P. ;

Buehler, R. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caragiulo, M. ;

Caraveo, P. A. ;

Cavazzuti, E. ;

Cecchi, C. ;

Charles, E. ;

Chekhtman, A. ;

Chiang, J. ;

Chiaro, G. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Conrad, J. ;

Cuoco, A. ;

Cutini, S. ;

D'Ammando, F. ;

de Angelis, A. ;

de Palma, F. ;

Dermer, C. D. ;

Digel, S. W. ;

do Couto e Silva, E. ;

Drell, P. S. ;

Favuzzi, C. ;

Ferrara, E. C. ;

Focke, W. B. ;

Franckowiak, A. ;

Fukazawa, Y. ;

Funk, S. ;

Fusco, P. ;

Gargano, F. .

ASTROPHYSICAL JOURNAL, 2015, 799 (01)

[7] THE SPECTRUM AND MORPHOLOGY OF THE FERMI BUBBLES [J].

Ackermann, M. ;

Albert, A. ;

Atwood, W. B. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Bastieri, D. ;

Bellazzini, R. ;

Bissaldi, E. ;

Blandford, R. D. ;

Bloom, E. D. ;

Bottacini, E. ;

Brandt, T. J. ;

Bregeon, J. ;

Bruel, P. ;

Buehler, R. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caragiulo, M. ;

Caraveo, P. A. ;

Cavazzuti, E. ;

Cecchi, C. ;

Charles, E. ;

Chekhtman, A. ;

Chiang, J. ;

Chiaro, G. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Conrad, J. ;

Cutini, S. ;

D'Ammando, F. ;

de Angelis, A. ;

de Palma, F. ;

Dermer, C. D. ;

Digel, S. W. ;

Di Venere, L. ;

do Couto e Silva, E. ;

Drell, P. S. ;

Favuzzi, C. ;

Ferrara, E. C. ;

Focke, W. B. ;

Franckowiak, A. ;

Fukazawa, Y. ;

Funk, S. ;

Fusco, P. ;

Gargano, F. ;

Gasparrini, D. ;

Germani, S. .

ASTROPHYSICAL JOURNAL, 2014, 793 (01)

[8] FERMI-LAT OBSERVATIONS OF THE DIFFUSE γ-RAY EMISSION: IMPLICATIONS FORCOSMIC RAYS AND THE INTERSTELLAR MEDIUM [J].

Ackermann, M. ;

Ajello, M. ;

Atwood, W. B. ;

Baldini, L. ;

Ballet, J. ;

Barbiellini, G. ;

Bastieri, D. ;

Bechtol, K. ;

Bellazzini, R. ;

Berenji, B. ;

Blandford, R. D. ;

Bloom, E. D. ;

Bonamente, E. ;

Borgland, A. W. ;

Brandt, T. J. ;

Bregeon, J. ;

Brigida, M. ;

Bruel, P. ;

Buehler, R. ;

Buson, S. ;

Caliandro, G. A. ;

Cameron, R. A. ;

Caraveo, P. A. ;

Cavazzuti, E. ;

Cecchi, C. ;

Charles, E. ;

Chekhtman, A. ;

Chiang, J. ;

Ciprini, S. ;

Claus, R. ;

Cohen-Tanugi, J. ;

Conrad, J. ;

Cutini, S. ;

de Angelis, A. ;

de Palma, F. ;

Dermer, C. D. ;

Digel, S. W. ;

do Couto e Silva, E. ;

Drell, P. S. ;

Drlica-Wagner, A. ;

Falletti, L. ;

Favuzzi, C. ;

Fegan, S. J. ;

Ferrara, E. C. ;

Focke, W. B. ;

Fortin, P. ;

Fukazawa, Y. ;

Funk, S. ;

Fusco, P. ;

Gaggero, D. .

ASTROPHYSICAL JOURNAL, 2012, 750 (01)

[9] WIMPs at the galactic center [J].

Agrawal, Prateek ;

Batell, Brian ;

Fox, Patrick J. ;

Harnik, Roni .

JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS, 2015, (05)

[10] Discovery of very-high-energy γ-rays from the Galactic Centre ridge [J].

Aharonian, F ;

Akhperjanian, AG ;

Bazer-Bachi, AR ;

Beilicke, M ;

Benbow, W ;

Berge, D ;

Bernlöhr, K ;

Boisson, C ;

Bolz, O ;

Borrel, V ;

Braun, I ;

Breitling, F ;

Brown, AM ;

Chadwick, PM ;

Chounet, LM ;

Cornils, R ;

Costamante, L ;

Degrange, B ;

Dickinson, HJ ;

Djannati-Ataï, A ;

Drury, LO ;

Dubus, G ;

Emmanoulopoulos, D ;

Espigat, P ;

Feinstein, F ;

Fontaine, G ;

Fuchs, Y ;

Funk, S ;

Gallant, YA ;

Giebels, B ;

Gillessen, S ;

Glicenstein, JF ;

Goret, P ;

Hadjichristidis, C ;

Hauser, D ;

Hauser, M ;

Heinzelmann, G ;

Henri, G ;

Hermann, G ;

Hinton, JA ;

Hofmann, W ;

Holleran, M ;

Horns, D ;

Jacholkowska, A ;

de Jager, OC ;

Khélifi, B ;

Klages, S ;

Komin, N ;

Konopelko, A ;

Latham, IJ .

NATURE, 2006, 439 (7077) :695-698

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