Axion mass limits may be improved by pulsar x-ray measurements
Axions thermally emitted by a neutron star would be converted into x rays in the strong magnetic field surrounding the star. The present observational limit of pulsed x rays from the Vela pulsar (PSR 0833-45) is not small enough to bound the axion mass. An increase in x-ray sensitivity by a factor of 10/sup 4/ would constrain the axion mass M-italic/sub a-italic/<3 x 10/sup -3/ eV if the core is nonsuperfluid and at temperature T-italic/sub c-italic/--2 x 10/sup 8/ K. This would improve the limits M-italic/sub a-italic/approx. <4 x 10/sup -2/ eV from neutron-star cooling and M-italic/sub a-italic/<1 x 10/sup -2/ eV from red-giant evolution. If the core is superfluid throughout, a factor of 10/sup 5/ in sensitivity would be needed. A search for modulated hard x rays from PSR 1509-58 or other young pulsars is suggested. A limit on pulsed hard x rays <5 x 10/sup -7/ photons/cm/sup 2/ sec from a very young hot (T-italic/sub c-italic/--7 x 10/sup 8/ K) pulsar within the Galaxy could set a firm bound on the axion mass, since neutron superfluidity is not expected above this temperature.
- Research Organization:
- Lawrence Berkeley Laboratory, University of California, Berkeley, California 94720
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 5649078
- Journal Information:
- Phys. Rev. D; (United States), Vol. 34:3
- Country of Publication:
- United States
- Language:
- English
Similar Records
Gamma-ray emission from young neutron stars. [PSR 1951+32; PSR 1855+09]
HEAO 3 upper limits to pulsed gamma-ray emission from PSR 1509 - 58 and PSR 0833 - 45
Related Subjects
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
AXIONS
MASS
PARTICLE PRODUCTION
PULSARS
X RADIATION
BREMSSTRAHLUNG
LUMINOSITY
MAGNETIC FIELDS
NEUTRON STARS
PHOTONS
UNIVERSE
BOSONS
COSMIC RADIO SOURCES
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
GOLDSTONE BOSONS
IONIZING RADIATIONS
MASSLESS PARTICLES
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
POSTULATED PARTICLES
RADIATIONS
STARS
640102* - Astrophysics & Cosmology- Stars & Quasi-Stellar
Radio & X-Ray Sources
645102 - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties