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A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
Published on: June 28, 2015
Geminga's tails: a pulsar bow shock probing the interstellar medium.
P A Caraveo1, G F Bignami, A DeLuca
1Istituto di Astrofisica Spaziale e Fisica Cosmica-Consiglio Nazionale della Richerche, Via Bassini, 15-20133 Milano, Italy. pat@mi.iasf.cnr.it
Science (New York, N.Y.)
|July 26, 2003
Summary
X-ray observations revealed two parallel tails trailing the pulsar Geminga, caused by its supersonic motion. This pulsar bow shock detection offers insights into electron energy and magnetic fields.
Area of Science:
- Astrophysics
- High-energy astrophysics
- Plasma physics
Background:
- Pulsars are rapidly rotating neutron stars emitting beams of radiation.
- Pulsar wind nebulae are formed by the interaction of pulsar winds with the interstellar medium.
- Geminga is a nearby, isolated neutron star.
Purpose of the Study:
- To investigate the nature of the observed X-ray tails associated with the pulsar Geminga.
- To analyze the emission mechanism and physical properties of the X-ray tails.
- To use the X-ray detection of the pulsar bow shock to constrain astrophysical parameters.
Main Methods:
- Utilized data from the X-ray Multimirror Mission-Newton European Photon Imaging Camera (EPIC).
- Analyzed the morphology and spectral properties of the elongated X-ray tails.
- Modeled electron synchrotron emission within a bow shock structure.
Main Results:
- Observed two parallel X-ray tails trailing Geminga, aligned with its supersonic motion.
- The tails exhibit a nonthermal spectrum indicative of electron-synchrotron emission.
- Electron cooling times match the transit time across the observed X-ray features.
Conclusions:
- The X-ray tails represent a pulsar bow shock formed by Geminga's wind interacting with the interstellar medium.
- This detection allows estimation of the pulsar's electron injection energy and the shock's magnetic field.
- Constrained Geminga's motion angle and the density of the surrounding local matter.
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