the magnetic field of an isolated neutron star from x-ray cyclotron absorption lines g.f.bignami...
DESCRIPTION
INS results from XMM-Newton Puppis A PSR J PSR B RX JTRANSCRIPT
The Magnetic Field of an Isolated Neutron Star from X-ray Cyclotron Absorption Lines
G.F.Bignami (1,2)
P.A.Caraveo (3)
A.De Luca (3,4)
S.Mereghetti (3)(1) CESR, Toulouse, France
(2) Università di Pavia, Pavia, Italy
(3) CNR-IASF, Milano, Italy
(4) Università di Milano Bicocca, Milano, Italy
INS results from Chandra
PSR B0656+14
PSR B1055-52
Vela pulsarRX J0720.4-3125
INS results from XMM-Newton
Puppis A PSR J0030+0451
PSR B1055-52 RX J0720.4-3125
Then came 1E1207.4-5209
•Discovered by Einstein•Close to the center of SNR G296.5+10.0•“High” galactic latitude: b≈10°•SNR age: 7 kyears•SNR distance: 2 kpc
A radio-quiet INS candidate•Lack of optical counterpart•No radio source•BB-like X-ray spectrum
Radio-quiet INS?
NS nature confirmed by Chandra
P~424 ms (Zavlin et al.2000)
Estimate of Pdot (0.7-3.1)x10-14 s s-1 (Pavlov et al.2002)
Age Problem: τPSR >> τSNR
This INS was the first to show features in its spectrum
ChandraSanwal et al, 2002
Same dataHailey & Mori 2002
XMM-Newton Mereghetti et al, 2002
The latest EPIC view: 260 ksec
The deepest XMM-Newton galactic field
Phase-averaged spectroscopy
pn data
208,000 photons
MOS (1+2) data
151,300 photons
0.7 keV1.4 keV
2.1 keV 2.8 keV
Check for possible miscalibrations
Red: 3C273 Black: 1E1207.4-5209
0.7 1.4
2.1(2.8)
AuSi
Timing Analysis
Pulsed fraction ~ 7%
Phase-resolved spectroscopy
ConclusionsIF electron cyclotron: <B> 8 1010
IF proton <B> 1.6 1014
Problem with B as derived from timing parameters:
Current pdot:(1.4 0.3) 10-14 s/s implies B= 2-3 1012
but also implies an age of 5 105 years in contrast with the SNR age ( about 104 ys)
0.7 keV
1.4 keV 2.1 keV 2.8 keV