The fraction of DA white dwarfs with kilo-Gauss magnetic fields
| dc.creator | Jordan, S. | |
| dc.creator | Cuadrado, R. Aznar | |
| dc.creator | Napiwotzki, R. | |
| dc.creator | Schmid, H. M. | |
| dc.creator | Solanki, S. K. | |
| dc.date | 2006-10-30 | |
| dc.date | 2006-11-13 | |
| dc.date.accessioned | 2026-07-07T07:44:09Z | |
| dc.date.available | 2026-07-07T07:44:09Z | |
| dc.description | Weak magnetic field has been searched for on only a small number of white dwarfs. Current estimates for white dwarfs with fields in excess of 1MG are about 10%; according to previous studies this number increases up to about 25% in the kG regime. Our aim is to improve the statistics by a new sample of ten white dwarfs in order to determine the ratio of magnetic to field-free white dwarfs. Mean longitudinal magnetic fields strengths were determined by means of high-precision circular polarimetry of Hbeta and Hgamma with the FORS1 spectrograph of the VLT ``Kueyen'' 8 m telescope. In one of our objects (LTT 7987) we detected a statistically significant (97% confidence level) longitudinal magnetic field varying between (-1+-0.5$)kG and (+1+-0.5)kG. This would be the weakest magnetic field ever found in a white dwarf, but at this level of accuracy, systematic errors cannot completely be ruled out. We also observed the sdO star EC11481-2303 but could not detect a magnetic field. VLT observations with uncertainties of typically 1000 G or less suggest that 15-20% of WDs have kG fields. Together with previous investigations, the fraction of kG magnetic fields in white dwarfs amounts to about 11-15%, which is close to the current estimations for highly magnetic white dwarfs (>1MG). | |
| dc.description | 11 pages, 4 figures, accepted for publication in A&A | |
| dc.identifier | https://arxiv.org/abs/astro-ph/0610875 | |
| dc.identifier | http://arxiv.org/abs/astro-ph/0610875 | |
| dc.identifier | doi:10.1051/0004-6361:20066163 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/123091 | |
| dc.subject | Astrophysics | |
| dc.title | The fraction of DA white dwarfs with kilo-Gauss magnetic fields | |
| dc.type | text |