Astronomy and Astrophysics – Astrophysics
Scientific paper
2005-11-24
Mon.Not.Roy.Astron.Soc.Lett.367:L16-L19,2006
Astronomy and Astrophysics
Astrophysics
4 pages, 1 figure, accepted for publication in MNRAS Letters; small changes to match the published text
Scientific paper
10.1111/j.1745-3933.2005.00130.x
In the context of the ``missing metals problem'', the contributions of the UV-selected z=2.2 ``BX'' galaxies and z=2.5 ``distant red galaxies'' (DRGs) have not been discussed previously. Here we show that: (i) DRGs only make a marginal contribution to the metal budget (~ 5%); (ii) BX galaxies contribute as much as 18% to the metal budget; and (iii) the K-bright subsample ($K<20$) of the BX sample (roughly equivalent to the `BzK' selected samples) contributes roughly half of this 18%, owing both to their larger stellar masses and higher metallicities, implying that the rare K-bright galaxies at z>2 are a major source of metals in the budget. We showed in the first paper of this series that submm galaxies (SMGs) brighter than 3 mJy contribute ~5% (<9% as an upper limit) to the metal budget. Adding the contribution of SMGs and damped Ly-alpha absorbers, to the contribution of UV selected galaxies, implies that at least 30% of the metals (in galaxies) have been accounted for at z=2. The cosmic metal density thus accounted for is ~ 1.3\times 10^6 \rhosun. This is a lower limit given that galaxies on the faint-end of the luminosity function are not included. An estimate of the distribution of metals in local galaxies as a function luminosity suggests that galaxies with luminosity less than L^{\star}$ contribute about half of the total mass of metals. If the metals in galaxies at z ~ 2 are similarly distributed then faint galaxies alone cannot solve the `missing metals problem.' Galaxy populations at z ~ 2 only account for about 50% of the total metals predicted.
Bouché Nicolas
Lehnert Matt D.
Peroux Celine
No associations
LandOfFree
The missing metals problem: II. How many metals are in z ~ 2.2 galaxies? 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 The missing metals problem: II. How many metals are in z ~ 2.2 galaxies?, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The missing metals problem: II. How many metals are in z ~ 2.2 galaxies? will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-424333