Computer Science
Scientific paper
Dec 1997
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997hst..prop.7234e&link_type=abstract
HST Proposal ID #7234
Computer Science
Hst Proposal Id #7234 Cosmology
Scientific paper
The observed spectra of z 4 QSOs are similar to those of low z QSOs, implying significant chemical enrichment of oxygen {OVI, 1034A} and carbon {CIV, 1550A}. The possible existence of iron in these objects is particularly interesting because iron production is thought to be delayed 1 Gyr relative to elements such as oxygen, which are directly synthesized in massive stars. An age of 1 Gyr or more for z 4 sources would significantly constrain the Hubble constant {H_0}/deceleration parameter {q_0} space. Spectra of high redshift QSOs, if similar to their low-z counterparts, should exhibit two signatures of FeII emission detectable in the near infrared. These are due to a complex of permitted FeII multiplets extending from 2240 to 3500A {the "FeII bump"}, and include a broad FeII feature around 2800A. A comparison of the strong, narrow 2800A MgII line flux with the CIV and Ly_alpha lines {measured from the ground} allows an estimate of excitation effects in the QSO, and the comparison of MgII to FeII indicates the relative importance of alpha- and E-process nucleosynthesis. Two high redshift QSOs will be observed with both NICMOS grisms A and B to measure the FeII bump and both the FeII and MgII 2800A features, as well as the 1909A CIII line. The sensitivity is adequate to measure the broad FeII bump in one orbit per source.
No associations
LandOfFree
FeII and MgII Emission from Redshift 4 QSOs does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with FeII and MgII Emission from Redshift 4 QSOs, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and FeII and MgII Emission from Redshift 4 QSOs will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-895246