p. 1/11 a detailed morphology of the w 28 region at tev ... · p. 2/11 elisabeth b rion...

p. 1/11

Elisabeth BRION–TeVParticleAstrophysics, August 27-31, 2007, IstitutoVeneto, Venice

A d

eta

iled

Mo

rph

olo

gy

of

the W

28 R

eg

ion

at

TeV

En

erg

ies

as r

ev

eale

d b

y H

.E.S

.S.

E.

BR

ION

for

the

H.E

.S.S

. C

oll

ab

ora

tio

n

CEA-Saclay, DAPNIA

TeVParticle Astrophysics, August 27-31, 2007, IstitutoVeneto, Venice

p. 2/11


Th

e H

.E.S

.S.

Co

llab

ora

tio

n

MPI KernphysikHeidelberg

Humboldt Univ. Berlin

Ruhr-Univ. Bochum

Univ. Erlangen-Nürnberg

Univ. Hamburg

LSW Heidelberg

Univ. Tübingen

Ecole polytechnique Palaiseau

Univ. Paris VI –VII

APC Paris

CEA Saclay

Paris Observatory

Meudon

LAPP Annecy

Univ. Grenoble

Univ. Montpellier II

CESR Toulouse

Durham Univ.

Leeds Univ.

Dublin Inst. for Adv. Studies

NicolausCopernicusAstronomicalCenter

Warsaw

AstronomicalObservatoryCracow

Institute of PhysicsCracow

Institute of NuclearPhysicsCracow

SpaceResearchCentre W

arsaw

Charles Univ. Prag

YerevanPhysicsInstitute Yerevan

Univ. Adelaide

Univ. NamibiaWindhoek

NorthWest Univ. Republic

of South Africa

~ 3

0 in

sti

tute

s

~ 1

30

ph

ys

icis

tsa

nd

as

tro

ph

ys

icis

ts

(ma

inly

in F

ran

ce

an

d G

erm

an

y)

p. 3/11


H.E

.S.S

.

4 telescopes

individual mirrors 107 m

2

4 cameras 960 PMT

field of view 5°

Duty cycle (without Moon)

~1000 hr/yr

300 images/s

fastonline analysis

final analysisand calibration:

2 independentchains

(France + Germ

any)

Energythreshold: 100 GeV

Sensitivity:

1 %

Crabflux in 25 hr

p. 4/11


Th

e W

28 R

eg

ion

-SNR W

28(alsoG6.4-0.1):

centrally

filledin X-rays + shell-likeradio morphology

size

50'×

45'

age

~ 3.5 –

15 ×104yr

distance

~ 1.8 –

3.3 kpc

associatedwithGRO J1801-2320

-SeveralHII regionsand dense molecularcloudswith

highconcentration of OH masers (1720 MHz).

p. 5/11


Ob

se

rvati

on

s o

f th

e W

28 R

eg

ion

Inte

nsit

ym

ap

ob

tain

ed

by t

he V

LA

at

90 c

m.

In g

ree

n:

4-6

σ

H.E

.S.S

.

sig

nif

ica

nce

co

nto

urs

.

H.E.S.S. Hillas

analysis

parameters:

Image cuts

> 200

photoelectrons

(p.e.).

PSF ~ 0.1°.

Exposure: 42 hrs.

Gaussiansmooth

of σ= 4.2’.

[G. ROWELL, E. BRION,

et al., 30th ICRC, 2007.]

[F. AHARONIANet al.,

submittedto A&A.]

p. 6/11


(Pre

lim

inary

!)W

28 R

eg

ion

wit

hth

e «

Mo

del

+ H

illa

sA

naly

sis

»

Image cuts

> 60 p.e.

PSF:

R = 0.07°

athalfmax.

Exposure:

50.3 hr.

Map

oversampling

of 0.07°.

In black: 3-6 σ

significance

contours.

HE

SS

J180

1-2

33

HE

SS

J180

0-2

40

A

B

C

H.E

.S.S

.

Exces

sm

ap

obtainedwith

the M

odel

analysisgiving

a lower

thresholdand

a better

sensitivityat

lowenergies.

[Description of

thisanalysisin

M. DENAUROIS,

astro-

ph/0607247,

2006.]

p. 7/11


Mo

rph

olo

gy s

ee

ms E

nerg

y

dep

en

den

tE

<0

.8 T

eV

E >

0.8

Te

V

Ex

ce

ss

ma

ps

wit

hlo

we

ne

rgy

sig

nif

ica

nc

ec

on

tou

rs 3

-6 σ

in b

lac

k.

HE

SS

J180

1-2

33

HE

SS

J180

0-2

40

A

B

C

HE

SS

J180

1-2

33

HE

SS

J180

0-2

40

A

B

C

p. 8/11


HE

SS

J180

1-2

33

: E

xcess M

ap

sE

<0

.8 T

eV

: 7

.7 σ

ex

ce

ss

(37

5 γ

)E

>0

.8 T

eV

: 5

.2 σ

ex

ce

ss

(14

0 γ

)

Co

nto

urs

fro

mh

alf

-ma

x t

o m

ax

of

the

ma

in p

ea

k:

low

en

erg

yin

bla

ck

,

hig

he

ne

rgy

in w

hit

e.

HE

SS

J180

1-2

33

HE

SS

J180

1-2

33

Ma

in S

po

t S

ize

= O

(PS

F)

p. 9/11


(Pre

lim

inary

!)H

ES

S J

1801

-233

Po

wer

Law

Sp

ectr

um

Fit

Wit

hH

illa

san

aly

sis

, w

ith

in0.2

°:

Sp

ectr

al

ind

ex 2

.7 ±

0.3

sta

t

Flu

x Ф

(1 T

eV

) ≈

10

-12

cm

-2s

-1T

eV

-1

Wit

h«

Mo

del +

Hilla

san

aly

sis

»,

wit

hin

0.1

2°:

Sp

ectr

al

ind

ex 2

.4 ±

0.3

sta

t

Flu

x Ф

(E >

300 G

eV

)

= (

1.3

±0.3

) × ×××

10

-12

cm

-2s

-1

(≈1 %

Cra

bfl

ux)

Flu

x Ф

(1 T

eV

) ≈

4 × ×××

10

-13

cm

-2s

-1T

eV

-1

p. 10/11


HE

SS

J18

00

-24

0C

G5.7

1-0

.08

HE

SS

J180

0-2

40C

H.E

.S.S

. e

xc

es

s

ma

p

wit

h

VL

A

ob

se

rva

tio

ns

a

t 90

cm

(b

lack

co

nto

urs

) fr

om

C.

L.

BR

OG

AN

et

al.,

Ap

J63

9,

20

06

. T

he

H

.E.S

.S.

ex

ce

ss

co

inc

ide

sw

ith

the

ra

dio

SN

R c

an

did

ate

G5

.71-0

.08

.

p. 11/11


Su

mm

ary

�HESS J1801-233:the main spot is

compact with

a

moderately

hard spectral index (2.4 ±

0.3

stat). Another

weakerspot isdetectedat4.7 σ

but visible atlow

energy

only, implyinga softerenergyspectrum(to beconfirm

ed).

�HESS J1800-240:the overallmorphologyof thisextended

and complexemissionregionalsoappears

to vary

with

energy.

�HESS J1800-240C:the compact TeV

source is

spatially

coincidentwiththe newlyproposedSNR candidate G

5.71-

0.08.

p. 12/11


[G. ROWELL, E. BRION, et al., 30th ICRC, 2007.]

[F. AHARONIANet al., submittedto A&A.]

Ob

se

rvati

on

s o

f th

e W

28 R

eg

ion

NA

NT

EN

ob

serv

ati

on

s.

In g

ree

n:

4-6

σH

.E.S

.S. sig

nif

ica

nc

eco

nto

urs

.

p. 1/11 a detailed morphology of the w 28 region at tev ... · p. 2/11 elisabeth b rion...

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