H.E.S.S. Sources in H.E.S.S. Sources in IceCubeIceCube

Michelangelo D’AgostinoMichelangelo D’Agostino

PSU Analysis WorkshopPSU Analysis Workshop

June 21-24, 2006June 21-24, 2006

MethodMethod

the idea is to look for an excess of downgoing the idea is to look for an excess of downgoing muons generated by incoming gamma-ray muons generated by incoming gamma-ray showers (like the recent SGR analysis)showers (like the recent SGR analysis)

based on calculations done by Halzen and based on calculations done by Halzen and Hooper, JCAP 08 (2003) 006Hooper, JCAP 08 (2003) 006

H.E.S.S. has begun to map the Southern H.E.S.S. has begun to map the Southern gamma sky since then, so let’s re-evaluate in gamma sky since then, so let’s re-evaluate in light of what they’ve learnedlight of what they’ve learned

install an online filter for any sources that install an online filter for any sources that may look promisingmay look promising

maybe one of these sources would be good maybe one of these sources would be good for calibration of our pointing (cf. the moon for calibration of our pointing (cf. the moon shadow)shadow)

MethodMethod

)cos/()cos/(

1

cos

1014.2)(

5

E

E

EEEN

MC parameterization of the MC parameterization of the number of muons with energy number of muons with energy greater than Egreater than Eμμ produced by a produced by a gamma of energy Egamma of energy Eγγ

the muons have to reach the detector the muons have to reach the detector with energy above thresholdwith energy above threshold

what’s the minimum energy what’s the minimum energy at the surface, at the surface, Eμ,sur, a muon must have to reach and trigger the detector as a function of zenith?

EdX

dE

MethodMethod

thrE

ER

ln

1

00°° 0.5610.561

1010°° 0.5700.570

2020°° 0.6010.601

3030°° 0.6600.660

4040°° 0.7650.765

5050°° 0.9620.962

6060°° 1.3911.391

7070°° 2.7382.738

8080°° 16.54616.546

Zenith Eμ,sur (TeV)

MethodMethod

parameterize the gamma source parameterize the gamma source spectrum asspectrum as

then the number of muons then the number of muons reaching the detector depth from reaching the detector depth from the source isthe source is

1121210 TeVscmE

F

dE

dN

max,

min,

)()( ,,

E

E

sursur EENdE

dNdEEN

MethodMethod

taketake

53.0

,

04.0

cos/

surEf

fE

E

E

Fscm

sur

min,

max,

,

1217 ln)cos/(

1

cos102

where

surEE ,min, 10

MethodMethod

need background to calculate a need background to calculate a significancesignificance

thenthen

tNbkg23.2)(cos5.0

/ln

)(cos106.1'#

min,

max,

53.0,

68.216

tAE

E

E

F

N

Ns eff

surbkg

sig

ResultsResults

H.E.S.S. CatalogH.E.S.S. Catalog

23 published southern 23 published southern hemisphere sourceshemisphere sources

quite a few have unknown optical quite a few have unknown optical or x-ray counterparts (many in or x-ray counterparts (many in the galactic plane)the galactic plane)

others are previously know others are previously know pulsars, SNR’s, and AGN’spulsars, SNR’s, and AGN’s

RX J1713.7-RX J1713.7-39463946

~66%~66% 50.2550.25°° 2.192.19

PKS 2155-304PKS 2155-304 up to 50%up to 50% 59.7859.78°° 2.842.84

HESS J1614-518HESS J1614-518 ~25%~25% 38.1838.18°° 2.462.46

HESS J1804-216HESS J1804-216 ~25%~25% 68.3068.30°° 2.722.72

HESS J1616-508HESS J1616-508 ~19%~19% 39.1039.10°° 2.352.35

HESS J1825-137HESS J1825-137 ~17%~17% 76.2476.24°° 2.462.46

HESS J1303-631HESS J1303-631 ~17%~17% 26.8026.80°° 2.442.44

MSH 15-52/MSH 15-52/

PSR B1509-58PSR B1509-58~15%~15% 30.8430.84°° 2.272.27

HESS J1837-069HESS J1837-069 ~13%~13% 83.0683.06°° 2.272.27

HESS J1632-478HESS J1632-478 ~12%~12% 42.1842.18°° 2.122.12

PSR B1259-63PSR B1259-63 up to 10%up to 10% 26.1726.17°° 2.72.7

Source Flux in Crabs Zenith Spectral IndexH.E.S.S. CatalogH.E.S.S. Catalog

RX J1713.7-3946RX J1713.7-3946

A little depressing, but…

Emax=100 TeV

RX J1713.7-3946RX J1713.7-3946

Emax=1,000 TeV

Emax=1,000,000 TeV

This source is only ~1 kpc away, and it’s recently been confirmed as the only known proton

accelerator.

PKS 2155-304PKS 2155-304All the following plots are for Emax=1,000,000 TeV

HESS J1614-518HESS J1614-518

HESS J1804-216HESS J1804-216

Very inclined: 68°°

HESS J1616-508HESS J1616-508

HESS J1303-631HESS J1303-631

ConclusionsConclusions

doesn’t look tremendously doesn’t look tremendously promising for an actual detection promising for an actual detection of a steady point source of of a steady point source of gammasgammas

such a method could be useful for such a method could be useful for transient sources like hard, short transient sources like hard, short GRB’s in the southern hemisphereGRB’s in the southern hemisphere