WIMPs at the Galactic Center

Agrawal, Prateek; Batell, Brian; Fox, Patrick J.; Harnik, Roni

doi:10.1088/1475-7516/2015/05/011

Article
Report number	arXiv:1411.2592 ; FERMILAB-PUB-14-411-T ; CERN-PH-TH-2014-219 ; FERMILAB-PUB-14-411-T ; CERN-PH-TH-2014-219
Title	WIMPs at the Galactic Center
Author(s)	Agrawal, Prateek (Fermilab) ; Batell, Brian (CERN) ; Fox, Patrick J. (Fermilab) ; Harnik, Roni (Fermilab)
Publication	2015-05-07
Imprint	10 Nov 2014
Number of pages	34
Note	26 pages, 10 figures, 1 table
In:	JCAP 05 (2015) 011
DOI	10.1088/1475-7516/2015/05/011
Subject category	Particle Physics - Phenomenology
Abstract	Simple models of weakly interacting massive particles (WIMPs) predict dark matter annihilations into pairs of electroweak gauge bosons, Higgses or tops, which through their subsequent cascade decays produce a spectrum of gamma rays. Intriguingly, an excess in gamma rays coming from near the Galactic center has been consistently observed in Fermi data. A recent analysis by the Fermi collaboration confirms these earlier results. Taking into account the systematic uncertainties in the modelling of the gamma ray backgrounds, we show for the first time that this excess can be well fit by these final states. In particular, for annihilations to $(WW, ZZ, hh, tt)$, dark matter with mass between threshold and approximately (165, 190, 280, 310) GeV gives an acceptable fit. The fit range for $b\bar{b}$ is also enlarged to 35 GeV$\lesssim m_\chi \lesssim$ 165 GeV. These are to be compared to previous fits that concluded only much lighter dark matter annihilating into $b$, $\tau$, and light quark final states could describe the excess. We demonstrate that simple, well-motivated models of WIMP dark matter including a thermal-relic neutralino of the MSSM, Higgs portal models, as well as other simplified models can explain the excess.
Copyright/License	publication: © 2015-2025 The Author(s) (License: CC-BY-3.0), sponsored by SCOAP³ preprint: © 2014-2025 CERN (License: CC-BY-3.0)

$\emph{Left:} The $\gamma$-ray spectrum produced by a single $W$, $Z$, Higgs boson, and top quark, decaying at rest, weighted by $E_\gamma^2$. \emph{Right:} The residual spectrum of the Galactic center excess taken from \cite{Calore:2014xka}. The error bars only show the diagonal part of the covariance matrix, and have a large degree of correlation between them. We also show the four best-fit spectra from the Fermi analysis~\cite{simonatalk} which fit the excess well. We will dub these, from softest to hardest, as Fermi spectra (a) through (d). The normalization $\mathcal{N}$ corrects for the difference in the region of interest between the two analyses.$ $\emph{Left:} The $\gamma$-ray spectrum produced by a single $W$, $Z$, Higgs boson, and top quark, decaying at rest, weighted by $E_\gamma^2$. \emph{Right:} The residual spectrum of the Galactic center excess taken from \cite{Calore:2014xka}. The error bars only show the diagonal part of the covariance matrix, and have a large degree of correlation between them. We also show the four best-fit spectra from the Fermi analysis~\cite{simonatalk} which fit the excess well. We will dub these, from softest to hardest, as Fermi spectra (a) through (d). The normalization $\mathcal{N}$ corrects for the difference in the region of interest between the two analyses.$ $Spectra of photons arising from $\chi\chi \to hh$ ($\chi\chi \to b\bar{b}$) annihilation shown in dashed red (solid yellow) for a number of different masses of the dark matter.$ Show more plots

Corresponding record in: Inspire

Back to search

Record created 2014-11-13, last modified 2024-02-06

Registos similares

Article from SCOAP3: