A new measurement of the baryonic fraction using the sparse NGC 3258 group of galaxies

Kristian Pedersen, Y. Yoshii, J. Sommer-Larsen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

New X-ray observations of the sparse NGC 3258 group of galaxies made by the ASCA satellite with good spectral and spatial resolution has revealed that this group has a gravitational potential deep enough to prohibit significant mass removal from the system. The baryonic fraction within 240 h(50)(-1) kpc is found to be 0.065(-0.020)(+0.051) for h(50) = 1, where h(50) = H-0/50 km s(-1) Mpc(-1), in good agreement with the universal value of 0.05 +/- 0.01 predicted by standard big bang nucleosynthesis for a universe with Omega(0) = 1 and h(50) = 1. Since the deep potential of the NGC 3258 group ensures that all pristine intragroup gas has been retained, the baryonic fraction of the NGC 3258 group is indicative of the universal value. Consequently, it seems premature to rule out a critical universe.
Original languageEnglish
JournalAstrophysical Journal
Volume485
Pages (from-to)L17-L21
ISSN0004-637X
DOIs
Publication statusPublished - 1997

Fingerprint Dive into the research topics of 'A new measurement of the baryonic fraction using the sparse NGC 3258 group of galaxies'. Together they form a unique fingerprint.

Cite this