Searching for gamma-ray emission from galaxy clusters at low redshift

ABSTRACT We report the identification of a positive cross-correlation signal between the unresolved gamma-ray emission, measured by the Fermi Large Area Telescope, and four different galaxy cluster catalogues. The selected catalogues peak at low-redshift and span different frequency bands, including infrared, optical, and X-rays. The signal-to-noise ratio of the detected cross-correlation amounts to 3.5 in the most significant case. We investigate and comment about its possible origin, in terms of compact gamma-ray emission from AGNs inside clusters or diffuse emission from the intracluster medium. The analysis has been performed by introducing an accurate estimation of the cross-correlation power-spectrum covariance matrix, built with mock realizations of the gamma and galaxy cluster maps. Different methods to produce the mock realizations starting from the data maps have been investigated and compared, identifying suitable techniques which can be generalized to other cross-correlation studies.

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Bounds on WIMP dark matter from galaxy clusters at low redshift

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa1127 ◽

2020 ◽

Cited By ~ 2

Author(s):

Xiuhui Tan ◽

Manuel Colavincenzo ◽

Simone Ammazzalorso

Keyword(s):

Dark Matter ◽

Cross Section ◽

Cross Correlation ◽

Massive Particle ◽

Galaxy Cluster ◽

Branching Ratios ◽

Accurate Estimation ◽

X Rays ◽

Error Covariance ◽

Γ Ray

Abstract In this work we study the cross-correlation between Fermi-LAT diffuse γ-ray maps and galaxy cluster catalogues in order to search for a diffuse dark matter signal. We employ an accurate estimation of the error covariance matrix and we select 4 galaxy cluster catalogues at low-redshift 0 < z < 0.2 with large-halo mass M500 > 1013M⊙ including infrared, optical and X-rays wavebands. We consider weakly interacting massive particle (WIMP) dark matter with 100% branching ratios into τ+τ−, $b\bar{b}$, W+W− and μ+μ−. No evidence for a WIMP dark matter signal is identified, and we derive competitive bounds. The WIMP thermally averaged cross section is excluded at 95% C.L. for dark matter masses below 20 GeV and annihilation in the τ+τ− channel.

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A large area diamond-based beam tagging hodoscope for ion therapy monitoring

EPJ Web of Conferences ◽

10.1051/epjconf/201817009005 ◽

2018 ◽

Vol 170 ◽

pp. 09005 ◽

Cited By ~ 4

Author(s):

M.-L. Gallin-Martel ◽

L. Abbassi ◽

A. Bes ◽

G. Bosson ◽

J. Collot ◽

...

Keyword(s):

Detection Efficiency ◽

Signal To Noise Ratio ◽

Therapy Monitoring ◽

Chemical Vapor ◽

X Rays ◽

Reaction Products ◽

Large Area ◽

Position Measurement ◽

Set Up ◽

Good Signal

The MoniDiam project is part of the French national collaboration CLaRyS (Contrôle en Ligne de l’hAdronthérapie par RaYonnements Secondaires) for on-line monitoring of hadron therapy. It relies on the imaging of nuclear reaction products that is related to the ion range. The goal here is to provide large area beam detectors with a high detection efficiency for carbon or proton beams giving time and position measurement at 100 MHz count rates (beam tagging hodoscope). High radiation hardness and intrinsic electronic properties make diamonds reliable and very fast detectors with a good signal to noise ratio. Commercial Chemical Vapor Deposited (CVD) poly-crystalline, heteroepitaxial and monocrystalline diamonds were studied. Their applicability as a particle detector was investigated using α and β radioactive sources, 95 MeV/u carbon ion beams at GANIL and 8.5 keV X-ray photon bunches from ESRF. This facility offers the unique capability of providing a focused (~1 μm) beam in bunches of 100 ps duration, with an almost uniform energy deposition in the irradiated detector volume, therefore mimicking the interaction of single ions. A signal rise time resolution ranging from 20 to 90 ps rms and an energy resolution of 7 to 9% were measured using diamonds with aluminum disk shaped surface metallization. This enabled us to conclude that polycrystalline CVD diamond detectors are good candidates for our beam tagging hodoscope development. Recently, double-side stripped metallized diamonds were tested using the XBIC (X Rays Beam Induced Current) set-up of the ID21 beamline at ESRF which permits us to evaluate the capability of diamond to be used as position sensitive detector. The final detector will consist in a mosaic arrangement of double-side stripped diamond sensors read out by a dedicated fast-integrated electronics of several hundreds of channels.

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Constraints on the gamma-ray emission from the cluster-scale AGN outburst in the Hydra A galaxy cluster

Astronomy and Astrophysics ◽

10.1051/0004-6361/201219655 ◽

2012 ◽

Vol 545 ◽

pp. A103 ◽

Cited By ~ 6

Author(s):

◽

A. Abramowski ◽

F. Acero ◽

F. Aharonian ◽

A. G. Akhperjanian ◽

...

Keyword(s):

Gamma Ray ◽

Galaxy Cluster ◽

Gamma Ray Emission

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Some Interesting Work on Capillary Glass Detectors

Innovative Applications and Developments of Micro-Pattern Gaseous Detectors - Advances in Chemical and Materials Engineering ◽

10.4018/978-1-4666-6014-4.ch006 ◽

2014 ◽

pp. 103-113

Keyword(s):

Gamma Ray ◽

X Rays ◽

Glass Capillary ◽

Large Area ◽

Vacuum Technology ◽

Gas Atmosphere ◽

Gamma Ray Imaging ◽

Position Sensitive ◽

Primary Electrons ◽

Glass Detectors

In this chapter, the progress of the development of glass capillary plates is described. In some applications, capillary plates have advantages over GEM or other gaseous detectors. For example, they are compatible with vacuum technology allowing them to be used in sealed gaseous detectors. Prototypes of capillary plates combined with photocathodes sensitive to ultraviolet and visible light were the first to be developed and successfully tested. These detectors resemble vacuum imaging microchannel plates, widely used in many applications. However, the glass capillary plates operate in gas atmosphere and in avalanche mode. This offers a possibility to build large area position-sensitive photomultipliers since at atmospheric pressure there are no serious mechanical constrains on the window. Since glass has a high density, the capillary plate can also be used as efficient convertors of X-rays, and be used at the same time as a multiplication structure for the created primary electrons. Such a device is attractive for X-ray and gamma ray imaging and the first successful tests of a prototype of such a detector are described.

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Search for dark matter signatures in the gamma-ray emission towards the Sun with the Fermi Large Area Telescope

Physical Review D ◽

10.1103/physrevd.102.022003 ◽

2020 ◽

Vol 102 (2) ◽

Author(s):

M. N. Mazziotta ◽

F. Loparco ◽

D. Serini ◽

A. Cuoco ◽

P. De La Torre Luque ◽

...

Keyword(s):

Dark Matter ◽

Gamma Ray ◽

The Sun ◽

Large Area ◽

Gamma Ray Emission

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The Flare of 1989 September 9, 09:09 UT: Does Coronal Loop Collision Initiate Efficient Gamma-Ray Emission?

International Astronomical Union Colloquium ◽

10.1017/s0252921100078003 ◽

1994 ◽

Vol 142 ◽

pp. 707-711

Author(s):

H. Aurass ◽

A. Hofmann ◽

E. Rieger

Keyword(s):

Current Sheet ◽

Gamma Rays ◽

Coronal Loop ◽

Gamma Ray ◽

High Energy ◽

X Rays ◽

Subject Headings ◽

Γ Ray ◽

Gamma Ray Emission ◽

Magnetogram Data

AbstractVector magnetogram data and Hα pictures together with data published by Chupp et al. lead us to conjecture that in the presented case a contact between the rising two-ribbon flare current sheet and a coronal loop connecting two nearby plage regions initiates efficient high-energy γ-ray emission.Subject headings: Sun: corona — Sun: flares — Sun: X-rays, gamma rays

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Imaging in Hard X-ray Astronomy

Symposium - International Astronomical Union ◽

10.1017/s0074180900194173 ◽

2003 ◽

Vol 214 ◽

pp. 70-83 ◽

Cited By ~ 1

Author(s):

T. P. Li

Keyword(s):

Gamma Ray ◽

Signal To Noise Ratio ◽

High Energy ◽

High Signal ◽

Wide Field ◽

X Rays ◽

X Ray ◽

Energy Gamma ◽

High Resolution Images ◽

Energy Processes

The energy range of hard X-rays is a key waveband to the study of high energy processes in celestial objects, but still remains poorly explored. In contrast to direct imaging methods used in the low energy X-ray and high energy gamma-ray bands, currently imaging in the hard X-ray band is mainly achieved through various modulation techniques. A new inversion technique, the direct demodulation method, has been developed since early 90s. with this technique, wide field and high resolution images can be derived from scanning data of a simple collimated detector. The feasibility of this technique has been confirmed by experiment, balloon-borne observation and analyzing simulated and real astronomical data. Based the development of methodology and instrumentation, a high energy astrophysics mission – Hard X-ray Modulation Telescope (HXMT) has been proposed and selected in China for a four-year Phase-A study. The main scientific objectives are a full-sky hard X-ray (20–200 keV) imaging survey and high signal-to-noise ratio timing studies of high energy sources.

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Quiescent Magnetar Emission: Resonant Compton Upscattering

Symposium - International Astronomical Union ◽

10.1017/s0074180900181136 ◽

2004 ◽

Vol 218 ◽

pp. 267-270

Author(s):

Matthew G. Baring

Keyword(s):

Compton Scattering ◽

Gamma Ray ◽

Stellar Surface ◽

X Rays ◽

Polar Cap ◽

Inverse Compton Scattering ◽

Strong Fields ◽

Inverse Compton ◽

Gamma Ray Emission

A principal candidate for quiescent non-thermal gamma-ray emission from magnetars is resonant inverse Compton scattering in the strong fields of their magnetospheres. This paper outlines expectations for such emission, formed from non-thermal electrons accelerated in a pulsar-like polar cap potential upscattering thermal X-rays from the hot stellar surface. The resultant spectra are found to be strikingly flat, with fluxes and strong pulsation that could be detectable by GLAST.

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X-Ray Astronomy Satellite Ginga

International Astronomical Union Colloquium ◽

10.1017/s0252921100076880 ◽

1990 ◽

Vol 123 ◽

pp. 41-48

Author(s):

F. Makino

Keyword(s):

Gamma Ray ◽

Effective Area ◽

X Rays ◽

Scientific Instruments ◽

Large Area ◽

Gamma Ray Burst ◽

X Ray ◽

Proportional Counters ◽

Main Instrument

AbstractThe X-ray astronomy satellite Ginga carries three scientific instruments, the Large Area proportional Counters (LAC), All Sky X-ray Monitor (ASM) and Gamma-ray Burst Detector (GBD). The LAC is the main instrument with an effective area of 4000 cm2 giving it the highest sensitivity to hard X-rays so far achieved. Ginga observed about 250 targets up to the end of 1989.

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