14th Int. School, Erice 2004 1

MAGIC sensitivity

for pulsed emission from -ray

pulsars

R. de los Reyes & J.L. Contreras

Universidad Complutense de Madrid (U.C.M.)

14th Int. School, Erice 2004 2

Contents

-ray detection from pulsarsPulsar models MAGIC effective area

Gammas (5-200 GeV) and protons.Effect of Earth’s magnetic field.

SensitivityPulsar observation times

Conclusions

14th Int. School, Erice 2004 3

-ray detection from pulsars

EGRET (30MeV-30GeV):

271 detected sources

• 168 unidentified.

• 7 high-confidence pulsars.

Cherenkov telescopes (E>80 GeV):

Crab unpulsed component

Crab nebula

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Pulsar modelsPulsar γ spectra cutoffs. Two models:

•Polar Cap: Ecutoff ~ 10 GeV

•Outer gap: Ecutoff ~ 100 GeV.

MAG

IC

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MAGIC effective areaGammas (5-200 GeV)

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Effect of Earth’s magnetic field

2222coscossin zxzx BBBBB -

B @ -ray observatory:

• Bx, Bz = f(L, f, h)

(-observatory longitude, latitude and altitude)

S E N W

S

N

S W N E

z

x

B

Btg min

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B and gamma effective areas

14th Int. School, Erice 2004 9

Sensitivity

(Nel & de Jager, 1996)

(Wiebel, PhD thesis, 1998)

)(.

stR

RQN obs

backg

s

dEEAdE

dNHzR eff

E

)()(0

Gamma and proton fluxes (dN/dE):

PulsarR(Hz) (=10)

culm

()E00

(GeV)(GeV)

tobs(hour)

(Q=1, 5s)

(Rp=70Hz)

Crab 0.25 7 30 30

PSR1951+32

0.30 4 40 20

Geminga 0. 11 5

PSR1706-44 0.43 73 -- ---

PSR1055-52 0.02 81 -- ---

Vela 3x10-4 74 -- ---

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Observation times(5s, Q=1)

Crab (=2.08) PSR1951+32 (=1.74)

(b = 2)

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Sensitivity with B

Pulsar

R(Hz) (=45)

tobs(hour)

(Q=1, 5s) (Rp=70Hz)

f=0 (South)

f=180 (North)

f=0 (South)

f=180 (North)

Crab 0.25 0.10 30 181

PSR1951+32 0.30 0.14 20 96

Geminga 0. 0.

PSR1706-44 0.43 0.20 --- ---

PSR1055-52 0.02 0.006 --- ---

Vela 3x10-4 9x10-5 --- ---

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ConclusionsMAGIC will cover part of the -spectrum of pulsars.Large Aeff: possible discovery of new pulsars.Observation of pulsed emission would discriminate between pulsed emission models in ’s.B affects the sensitivity depending on the location and the energy threshold of the telescope Location of new gamma observatories (Ethreshold lower).At La Palma: important for primary gammas and electrons (>30 and E100 GeV), and negligible for protons pulsars (tobs 20%).

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Quality factor improvement

Q 2.5

Q = 3 (Crab)

/hadron separation techniques

P known previously

3333~ msmsQ

Ona-Wilhelmi et al, (private communication)

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Lateral distributions: gammas

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MAGIC effective areaGammas (5-200 GeV)

Protons (30 GeV-30 TeV)