Cosmic Gamma-ray Background Radiation - NASA

Star-forming GalaxiesAckermann et al.The Astrophysical Journal, 755:164 (23pp), 2012 August 20SFR (M yr -1)4310110310210LAT Non-detected (Upper Limit)LAT Non-detected with AGN (Upper Limit)1042L0.1-100 GeV (erg s-1)10-14110LAT DetectedLAT Detected with AGNArp 220Best-fitFit UncertaintyDispersionNGC 2146NGC 1068Calorimetric Limit50(E η 10 erg)M82SN4010M831039M31NGC 4945NGC 253NGC 6946IC 342Milky WayM33103810Power Law Γ 2.2, 0 z 2.510-710-8LMC1037SMC89101010111010L8-1000 µm (L )Isotropic DiffuseStar-forming GalaxiesMilky Way Spectrum, 0 z 2.5-6E2 dN/dE (GeV cm-2 s-1 sr -1)10-21210Thompson et al. 2007 (Γ 2.2)Fields et al. 2010 (Density-evolution)Fields et al. 2010 (Luminosity-evolution)Makiya et al. 2011Stecker & Venters 2011 (IR)Stecker & Venters 2011 (Schecter)10-1Ackermann ’121E (GeV)10102Ackermann ’12Figure 7. Estimated contribution of unresolved star-forming galaxies (both Soltan ’99; Pavlidou & Fields ’02; Thompson ’07; Bhattacharya& andSreekumaret diffuseal. 2010;Makiya etal. 2011;quiescentstarburst)2009;to 0101010110by theChakrabortyFermi-LAT (blackpoints;Abdoet al. 2010f). The shaded regions indicateStecker & Venters2011;Lien ’12,Ackermann ’12;Lacki ’12;& Fields’13;Tamborra ’14combined statistical and systematic uncertainties in the contributions of theLAT Non-detected (Upper Limit)-110LAT Non-detected with AGN (Upper Limit)respective populations. Two different spectral models are used to estimate theLAT DetectedGeV gamma-ray emission from star-forming galaxies: a power law with photon LAT Detected with AGNindex 2.2, and a spectral shape based on a numerical model of the global gammaBest-fitFit Uncertaintyray emission of the Milky Way (Strong et al. 2010). These two spectral models10-2Dispersionshould be viewed as bracketing the expected contribution since multiple starCalorimetric Limit forming galaxy types contribute, e.g., dwarfs, quiescent spirals, and starbursts.(E η 10 erg)-3We consider only the contribution of star-forming galaxies in the redshift range100 z 2.5. The gamma-ray opacity of the universe is treated using theextragalactic background light model of Franceschini et al. (2008). Several previous estimates for the intensity of unresolved star-forming galaxies are10-4SFR (M yr -1)L0.1-100 GeV / L8-1000 µmUse gamma-ray and infrared luminosity correlation 10-30% of CGB at 0.1-100 GeV.50SNNGC 2146But, only 10 sources are detected by Fermi.Arp 220M33M83NGC 253NGC 6946NGC 4945M82NGC 1068

Blazars, star-forming galaxies and radio galaxies can explain the intensityand the spectrum of the EGBComponents of Cosmic Gamma-ray BackgroundPreliminaryAjello at HEM14 usual: it does not include the systematic uncertainty on the EGB!FSRQs (Ajello ’12)As, BLLacs (Ajello ’14), Radio gals. (YI’11), & Star-forming gals. (Ackermann ’12) makes almost 100% of CGB from 0.1-1000 GeV. However, we need to assume SEDs at higher energies. See Di Mauro’s talk

Future CGB studies Anisotropy of Cosmic GeV Gamma-ray Background Cosmic MeV Gamma-ray Background Searching Dark Matter signatureOrigins are still unknown.Cosmic TeV Gamma-ray Background Connection to the IceCube TeV-PeV neutrinos

Anisotropy of Cosmic Gammaray Background

Anisotropy of Cosmic Gamma-ray BackgroundJOINT ANISOTROPY AND SOURCE COUNT CONSTRAINTS . . .PHYSICAL REVIEW D 86, 063004 (2012)Cp(E) MAGN FSRQ BLLACFermi-LATMAGNLISP Bl LacHSP Bl LacFSRQTOTCp [(cm-2 s-1 sr-1)2 sr]10-1810-1910-2010-21100101E [GeV]Cuoco ’1242Di Mauro ’14E Cp/( E) MAGN FSRQ BLLACFIG. 3 (color online). Left: Constraints on blazar logN-logS parameters (break flux, Sb , and faint-end slope,") from the intensityand anisotropy of the IGRB. Regions in which blazars provide 100% of the observed IGRB anisotropy and mean intensity in the1–10 GeV energy band are shown; the widths of the regions indicate the 68% confidence intervals. Below these regions blazarsoverproduce the anisotropy and mean intensity. Labeled contours show the fraction of the blazar contribution to the IGRB intensity.The best-fit 1! parameter region from the Fermi source count analysis [4] is marked,along with the best-fit Sb [4] (dot-dashed line).10-17Right: Expanded view around the region of parameter space in the left panel where blazars contribute 100% of both the measuredIGRB anisotropy and intensity.Anisotropy puts strong constraints on the evolutionary models ofblazars (Cuoco ’12, Harding & Abazajian ‘13). CGB anisotropy is well explainedby known radio-loud AGNachieved quite naturally since some proposed contributorsthe IGRB,such as star-forminggalaxies [8], arepopulations (Di Mauro ’14) - toexpectedSeeDonato’stalk.to contribute negligibly to the anisotropy. On10-18the other hand, this result implies strong constraints onsource populations with large intrinsic anisotropy.We emphasize that the anisotropy and intensity contribu4scenarios we test an alternative fit to the blazar logN-logSobtained by Stecker and Venters [13]. A notable feature ofthis alternative fit is that it can account for !60% of theIGRB intensity in the 1–10 GeV energy band. We havecalculated CP from the logN-logS of the Stecker andVenters model [13,14] and, using a threshold of 5:0 "Cp/( E)2 [(GeV cm-2 s-1 sr-1)2 sr] Fermi-LATMAGNLISP BL LacHSP BL LacFSRQTOT

Anisotropy & Dark MatterPHYSICAL REVIEW D 87, 123539 u ‘13Shirasaki ’14FIG. 16 (color online). The same as Fig. 11, but for the limits obtainedfrom the Galactic subhalos (dashed), extragalacticFIG. 4. The 68 % confidence level upper limits on ⟨σv⟩ as a function of DM mhalos (dot-dashed), and the sum of the two (solid). Thedot-dashed line is the same as the solid line in Fig. 11. The τ channel and the green regionregionshowstheupperboundfortheτdotted lines show the Galactic subhalo limits from each offour energy bins.Angular power spectra of CGB is a powerful tool to constrain theDM properties (e.g. Ando & Komatsu ’06, ’13). that the widthsof theshadedandregionsindicatemodeluncertainty. ebea new6M atheuppercurveisderivedbyourbenchmarkmodelwithM 10min powerful tool (e.g. Shirasaki ’14) - See Shirasaki’s talk.Galactic terms. As expected, the limits from either alone 6

Cosmic MeV Gamma-rayBackground

Cosmic X-ray/MeV Gamma-ray Background2E2 dN/dE [keV2 cm-2 s-1 keV-1 sr-1]10Seyfert (Ueda ’03)Compton-thick AGN (Ueda ’03)ITU08 Seyfert (Inoue ’08)FSRQ (Ajello ’09)BL Lac (Ajello thick AGNs?BL Lacs10-1100101102Photon Energy [keV]103104

Seyferts and Cosmic MeV Gamma-ray BackgroundE2 dN/dE (keV/cm2/s/sr) w/ nonthermalRequired non-thermalelectron distribution issimilar to that in solarflares and Earth’smagnetotail Magnetic reconnection-heated corona?(Liu, Mineshige, & Shibata ’02)thermalEnergy (keV) YI ’08ALMA may probe thecorona heating scenario(YI & Doi ’14, YI & Doi in prep.).

110102Energy [keV]310104E2dN/dE [10-2Blazars and Cosmic MeV Gamma-ray Background-410 as indicated inhe CXB and contribution of the FSRQs (blue region). The data points are different measurements of the diffuse background75; Gendreau et al. 1995; Watanabe et al. 1997; Weidenspointner et al. 2000; Revnivtsev et al. 2003; Ajello et al. 2008b). The dashed line iseyfert-like AGNs computed with the model of Gilli et al. (2007) arbitrarily multiplied by 1.1 to fit the CXB emission at 30 keV. The solidert-like and FSRQs. The spectrum of FSRQs has been modeled as a power-with a mean photon index of 1.6. The blue region represents therom the Monte Carlo realizations of best-fit parameter ranges. The magenta solid line represents the contribution of BL Lac-5objects whose10for clarity, but is, due to the low number of objects, 30% at any energy.10-210-1gure is available in the online journal.)Based on Swift-BAT10110-1110102Energy [keV]310104Ajello ’091010-1E2dN/dE [MeV cm-2 s-1 sr -1]RXTE - Revnivtsev et al. 2003Swift/BAT - Ajello et al. 2008FSRQs, this workGilli et al. 20071102310104510Energy [MeV]Nagoya balloon - Fukada et al. 1975ASCA - Gendreau et al. 1995SMM - Watanabe et al. 1997COMPTEL - Weidenspointner et al. 2000102E2dN/dE [keV cm-2 s-1 sr -1]Based on Fermi-LATNagoya balloon - Fukada et al. 1975SMM - Watanabe et al. 1997COMPTEL - Weidenspointner et al. 2000EGRET - Strong et al. 2004Swift/BAT - Ajello et al. 2008IGRB (Abdo et al. 2010b)IGRB Sources (Abdo et al. 2010b)Contribution of FSRQs10-210-310-410-510-210-1110210Energy [MeV]310104510Ajello ’12of FSRQs (blue region) to the CXB. The data are the same as in Figure 15, but in this case theSED11.ofContributionthe FSRQsofhasbeen modeledFigureunresolved(top) andwithtotal (resolved plus unresolved, bottom) FSRQs to the diffuse extragalactic background (blue lineion. The IC peak is located in the MeV region. The contribution of BL Lac objects is the sameas in Figure15 and isfunctionnot drawnhereto forby integratingthe luminositycoupledthe SED model derived in Section 5.3. The hatched band around the best-fit prediction shows tpresents the range of values obtained from the Monte Carlo realizations of best-fit parameter ranges.uncertainty while the gray band represents the systematic uncertainty.(A color version of this figure is available in the online journal.)gure is available in the online journal.) FSRQs contribute to the GeV gamma-ray background with apeak at 100 MeV (e.g. YI & Totani ’09, Ajello ’12)Qs assuming that their IC peak is locatede find that in this case FSRQs account forsion up to 10 MeV. While there is basicallyespect to the single power-law case belowre of the IC peak makes the contribution oflightly smaller around 1 MeV. We also noteeak beyond 10 MeV produces a negligibleRQ integral emission and thus this case ishe single power-law model.alyses shown here cover well the case ineither located at MeV or at GeV energiese.g., BL Lac objects and starburst galaxies make significant(double and single power-lawmodel,torespectively).We mustcontributionsthe IGRB intensity.therefore conclude that the contribution of FSRQs to the diffuse7. BEAMING:THEINTRINSIC fractionLUMINOSITY FUNCTIONemission is relevant and likelyaccounts fora substantialANDTHEPARENTPOPULATION(potentially 100%) of the CXB around 1 MeV. Interpretingthe CXB as a strong constraint,we deriveLthattheinpopulationThe luminositiesdefinedthis work are apparent isotropicluminosities.Sincethethe jetmoving at relativistic speedof FSRQ sampled by BATmust haveICmaterialpeak islocated(γ 1),Dopplertheboosted,luminosities are relatedin the MeV band in ordernot esbybackground at 10 MeV. Bhattacharya et al. (2009) recentlyreported for the FSRQs detected by EGRET aLmeanphoton δ p L,(21)index of 2.34 0.15. Since FSRQs have a mean photon index13of 1.6 in BAT, this implies already that the IC peak is locatedwhere L is the intrinsic (unbeamed) luminositykinematic Doppler factor!δ (γ γ 2 1 cos θ ) 1 ,where γ (1 β 2 ) 1/2 is the Lorentz factor and βvelocity of the emitting plasma. Assuming that thea Lorentz factor γ in the γ1 ! γ ! γ2 range thenDoppler factor is δmin γ2 1 (when θ 90 ) and tis δmax γ2 γ22 1 (when θ 0 ). We adopt a vathat applies to the case of jet emission from a rel Two components in gamma-ray spectra or two FSRQpopulations?

Cosmic MeV Gamma-ray Background “Anisotropy”-6Clp [(ph/cm2/s)2sr-1]1010-7Poisson term onlyFlim 1e-10erg/cm2/s10-8FSRQ10-910-10 Radio-quiet AGNs (Ueda ’03)Radio-quiet AGNs (Inoue ’08)Blazars (Ajello ’09)Astro-H/SGD0.1Seyfert1Energy [MeV]10YI ‘13bAstro-H (SGD) / future MeV satellites will distinguishSeyfert & blazar scenarios through anisotropy in the sky.

Cosmic TeV Gamma-rayBackground

Upper Limit on Cosmic Gamma-ray BackgroundCascadeIntrinsicULAbsorbedYI & Ioka ’12 Cascade component from VHE CGB can not exceed the Fermi data(Coppi & Aharonian ’97, YI & Ioka ’12, Murase ’12, Ackermann ’14). No or negative evolution is required - HBLs show negativeevolution (Ajello ’14).

orresponding IGB (solid) are shown for Γ 2.0 (thick) andΓ 2.14 (thin). The shaded rectangle indicates the IceCubeata [4]. The atmospheric muon neutrino background [21]nd the diffuse IGB data by Fermi /LAT [14] are depicted.IceCube Neutrinos and Cosmic Gamma-ray Background50#(FSRQ, flaring6/427 )"!"6/427 )"!)48#'!"!"# %&!"#&()* ,-. /012#%!"# !"46"!!")!"*!" (!"!", -./05'!"ν47 10 erg s 10 s-1IRBLR42&!"%!"Murase !"7.5pk10%'4Γ 30, γ 10 , tνL-1log [4πL(ε,Ω) erg s ], ) ! -./0 12#) 3#! 34#!5!"12101310141015101610171018E (eV)νDermer, Murase, & YI ’13Fig. 4 The luminosity spectrum of neutrinos of all flavors fromFSRQ with δD Γ 30, using parameters of a flaringFIG. 2: The same as Fig. 1, but for Γ 2.0 (thick) anandblazar given in Table 1. The radiation fields are assumedΓ 2.18 (thin) with the star-formation history [23]. 3(Murase ’13) isotropic with energy densities 3u BLR 0.026 erg cm for theBLR field, u IR 0.001 erg cm for the graybody IR field. Fors because ξz in Eqs. (2) and (4) is similar and cancelsthe scattered accretion-disk field, τ sc 0.01 is assumed. Theproton spectrum is described by a log-parabola function withut in obtaining Eq. (5). This conclusion largely holdslog-parabola width b 1 and principal Lorentz factorven if neutrinos and γ rays are produced at very high′7.5γ Γγ 10pkedshifts. Interestingly,our YI,resultsare applicableeven to& YIpk’14) . Separate single-, double- and multi-pion(e.g. Murase,& Dermer’14, Dermer, Murase,componentscomprising the neutrino luminosity spectrumnaccounted-for Galactic sources, since the diffuse IGBisproduced by the BLR field are shown by the light dottedresidual isotropic component obtained after subtractcurves for the photohadronic and β-decay neutrinos. Separate ng knowncomponents including diffuse Galactic emiscomponents of the neutrino spectra from photohadronicion. If we use the preliminary Fermi data, based oninteractionsthewith the synchrotron, BLR, IR, and scatteredExtragalactic pp scenario (galaxies or clusters) for IceCube events willprovide 30-100 % of CGB.Extragalactic pγ scenario (e.g. FSRQs) depends on the target photonspectra.- See Ahlers’ talk & Reimer’s talk.Fmn1flγsrsiir

Cosmic UV/optical/infraredBackground Radiation

Cosmic Optical & Infrared Background (COB & CIB)100I [nW/m2/sr]101StarsDustMadau & Pozzetti ’00 (HST)Elbaz et al. ’02 (ISO)Papovich et al. ’04 (Spitzer)Fazio et al. ’04 (Spitzer)Xu et al. ’05 (GALEX)Dole et al. ’06 (Spitzer)Frayer et al. ’06 (Spitzer)Gardner et al. ’00 (HST)Berta et al. ’11 (Hershel/PEP)Wright & Reese ’00 (DIRBE)Wright ’04 (DIRBE)Levenson et al. ’07 (DIRBE)Levenson & Wright ’08 (DIRBE)Bernstein ’07 (HST)Matsuoka et al. ’11 (Pioneer)Matsumoto et al. ’11 (IRTS)Matsuura et al. ’11 (AKARI)CambrØsy et al. ’01 (DIRBE)Dwek & Arendt ’98 (DIRBE)Gorijian et al ’00 (DIRBE)Finkbeiner et al ’00 (DIRBE)Hauser et al ’98 (DIRBE)Lagache et al ’00 (DIRBE)Edelstein et al ’00 (Voyger)Brown et al ’00 (HST/STIS)Albert et al ’08 (MAGIC)(X, zc) (1.0, 0.0)(X, zc) (50.0, 10.0)(X, zc) (100.0, 10.0)0.10.1110100[µm]100010000YI ‘13a

IN 46323–2094, USA. Institució Catalana de Recerca i EstudisAvançats (ICREA), Barcelona, Spain. 61Consorzio Interuniversitarioper la Fisica Spaziale (CIFS), I-10133 Torino, Italy. 62Dipartimentodi Fisica, Università di Roma “Tor Vergata,” I-00133 Roma, Italy.63Department of Physics, Center for Cosmology and Astro-ParticlePhysics, Ohio State University, Columbus, OH 43210, USA.Downloaded from www.sConstraints from Gamma rays*To whom correspondence should be addressed. E-mail:majello@slac.stanford.edu (M.A.); buehler@stanford.edu(R.B.); anita.reimer@uibk.ac.at (A.R.)†Present address: Naval Research Laboratory, Washington, DC20375, USA.LAT best fit -- 1 sigmaLAT best fit -- 2 sigmaFranceschini et al. 2008Finke et al. 2010 -- model CStecker et al. 2012 -- High OpacityStecker et al. 2012 -- Low OpacityKneiske et al. 2004 -- highUVKneiske et al. 2004 -- best fitKneiske & Dole 2010Dominguez et al. 2011Gilmore et al. 2012 -- fiducialAbdo et al. 201010210Energy [GeV ] SCIENCEVOL 33830 NOVEMBER 20125H.E.S.S. low energyME12 exclusion regionH.E.S.S. high energyH.E.S.S. contour(sys statlow full high)Direct measurements10z 1.010 -1 102H.E.S.S. full dataset1encemag.orgH.E.S.S. collaboration: The EBL iλ Fλ [ nW m-2 sr -1 ]nfitiesthedicurethez omTheonrity,weEBL50/rtedUniversity, 3-4-1, Okubo, Shinjuku, Tokyo 169-8555, Japan.38CNRS, IRAP, F-31028 Toulouse cedex 4, France. 39GAHEC,Université de Toulouse, UPS-OMP, IRAP, Toulouse, France.40Department of Astronomy, Stockholm University, SE-106 91Stockholm, Sweden. 41Istituto Nazionale di Fisica Nucleare,Sezione di Torino, I-10125 Torino, Italy. 42Department of Physicsand Department of Astronomy, University of Maryland, CollegePark, MD 20742, USA. 43Hiroshima Astrophysical Science Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 7398526, Japan. 44Istituto Nazionale di Fisica Nucleare, Sezione diRoma “Tor Vergata,” I-00133 Roma, Italy 45INTEGRAL ScienceData Centre, CH-1290 Versoix, Switzerland. 46Institute of Spaceτγγe dioireau,pussicanziacationeca,ennce,Re-z 1.0Galaxy countsAckermann ’13110λ [ µm ]Abramowski ’13Fig. 5. Flux density of the extragalactic backgroundlight versuswave1191 length. The 1σ (statistical) contours derived for several energy rangesare described in the top-right legend. The systematic uncertainty isadded quadratically to the statistical one to derive the H.E.S.S. contour. Lower limits based on galaxy counts and direct measurements arerespectively shown with empty upward and filled downward pointingDominguez ’13) from Gilmore et al. 2012). The region excluded bytriangles (extractedMeyer et al. (2012) with VHE spectra is represented by the dashed area.Fermi derived the COB opacity using the combined spectraof blazars (see also Gong & Cooray ’13,.Table 6. Measured normalization of the EBL optical depth, corresponding to the 1σ (statistical) contours shown in Fig. 5.H.E.S.S. derived the COB intensity using the combinedτ/τλ λλF (λ ) λF (λspectra of blazars.µmnW m srmeasuredFR08minmaxλmin 2λ max ) hFowoPa

Direct Measurements of COB & CIBNo. ]urnal, 736:119 (14pp), 2011 August 1Extragalactic Background Light Spectrum withMatsuoka et al.Pioneer 10/11Matsuoka ’11AKARITsumura ’13urements of the cosmic background (filled symbols) and the integrated brightness of galaxies (open symbols) at UV, optical, and near-IRc background measurements include the UV upper limits (blue arrows) at 0.10 µm obtained from the Voyager/UVS (Edelstein et al. 2000)HST/STIS (Brown et al. 2000), the claimed detections at optical wavelengths using the HST/WFPC2 (Bernstein 2007, green squares) and4. Spectrum of EBL and integrated light of galaxies. Filled plots show EBL by vausing the COBE/DIRBE [Gorjian et al. (2000), green diamonds; Wright (2001), purple diamonds; Cambrésy et al. (2001), blueFig.diamonds;monds; the wavelengths of these measurements are slightly shifted relative to each other for clarity] and the IRTS (Matsumoto etal. 2005,thisstudy, and open plots shows the integrated light of galaxies by deep observationtars are the Pioneer/IPP results of this work, while the red solid line with arrows between 0.8 and 4 µm represents the HESS upperlimits data. Solid curve shows a model spectrum of the integrated light of galawide-bandThe integrated brightness of galaxies come from the HST/STIS measurements at UV (Gardner et al. 2000, squares), the HDF compilationrest-frame K-band galaxy luminosity function up to redshift 4 (Domı́nguez et al. 2011dau & Pozzetti 2000, triangles), and the Spitzer/IRAC measurements at near-IR wavelengths (Fazio et al. 2004, diamonds). Pioneer 10/11 measurements are consistent with the galaxy countlower limit.this correlation to the higher Galactic latitude regions in Earth must be dit in case of AKARI’s detection limit of point sources (mK 19).Table 4COB Brightness and Mean DGL-to-100 µm Brightness Ratios ad0WavelengthCOB BrightnessDGL-to-100 µm Ratio ad0our method. However, this assumpti

Cosmic Gamma-ray Background Radiation Yoshiyuki Inoue (JAXA International Top Young Fellow @ ISAS/JAXA) 10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 . the universe while the bulk of the population (i.e., the low luminosity objects) are more abundant at later times. The range of measured distribution is determined by