HOW DEAD ARE DEAD GALAXIES? MID-INFRARED FLUXES OF QUIESCENT GALAXIES AT REDSHIFT 0.3 <z< 2.5: IMPLICATIONS FOR STAR FORMATION RATES AND DUST HEATING
Mattia FumagalliIvo LabbéShannon G. PatelMarijn FranxPieter van DokkumGabriel BrammerElisabete da CunhaN. M. Förster SchreiberMariska KriekRyan QuadriHans‐Walter RixDavid A. WakeKatherine E. WhitakerBritt LundgrenDanilo MarchesiniMichael V. MasedaIvelina MomchevaErica J. NelsonCamilla PacificiRosalind E. Skelton
65
Citation
89
Reference
10
Related Paper
Citation Trend
Abstract:
We investigate star formation rates (SFRs) of quiescent galaxies at high redshift (0.3 < z < 2.5) using 3D-HST WFC3 grism spectroscopy and Spitzer mid-infrared data. We select quiescent galaxies on the basis of the widely used UVJ color–color criteria. Spectral energy distribution (SED) fitting (rest-frame optical and near-IR) indicates very low SFRs for quiescent galaxies (sSFR ∼ 10−12 yr−1). However, SED fitting can miss star formation if it is hidden behind high dust obscuration and ionizing radiation is re-emitted in the mid-infrared. It is therefore fundamental to measure the dust-obscured SFRs with a mid-IR indicator. We stack the MIPS 24 μm images of quiescent objects in five redshift bins centered on z = 0.5, 0.9, 1.2, 1.7, 2.2 and perform aperture photometry. Including direct 24 μm detections, we find sSFR ∼ 10−11.9 × (1 + z)4 yr−1. These values are higher than those indicated by SED fitting, but at each redshift they are 20–40 times lower than those of typical star-forming galaxies. The true SFRs of quiescent galaxies might be even lower, as we show that the mid-IR fluxes can be due to processes unrelated to ongoing star formation, such as cirrus dust heated by old stellar populations and circumstellar dust. Our measurements show that star formation quenching is very efficient at every redshift. The measured SFR values are at z > 1.5 marginally consistent with the ones expected from gas recycling (assuming that mass loss from evolved stars refuels star formation) and well below that at lower redshifts.Keywords:
Spectral energy distribution
Circumstellar dust
Extinction (optical mineralogy)
Stellar mass
Photometric redshift
We model the spectral energy distribution (SED) from the mid-infrared to submillimeter of the ringlike disk of HR 4796A, the dustiest A-type star. We consider dust made of either coagulated but otherwise unaltered protostellar interstellar grains or grains that are highly processed in a protostellar/protoplanetary nebula with silicate dust annealed and carbon dust oxidized. Both types of dust are successful in reproducing the observed SED, provided that the grains are highly fluffy, with a vacuum volume fraction of ~90%. We find no evidence for the existence of a hot "zodiacal dust" component a few astronomical units from the star, which was suggested by previous workers to account for the 10 μm wavelength emission.
Spectral energy distribution
Circumstellar dust
Zodiacal light
Extinction (optical mineralogy)
Cite
Citations (45)
Circumstellar dust
Dust lane
Atmospheric Dust
Dark nebula
Mineral dust
Extinction (optical mineralogy)
Cite
Citations (0)
Circumstellar dust
Extinction (optical mineralogy)
Dust lane
Cite
Citations (35)
Numerical radiative transfer models are used to study circumstellar dust grains around the peculiar Be star HD 45677. The modeling technique is to fit the observed far-ultraviolet through far-infrared energy distribution with the energy distributions predicted for a spherical dust shell around a luminous hot star. Such a simultaneous multi-wavelength study makes it possible to strengthen constraints on dust-grain properties. It is found that the observations can be fitted with the emergent spectrum of a spherical shell consisting of a graphite–silicate mixture. The grain-size distribution is similar to that for diffuse cloud dust |$N(a) \approx A \enspace a^{-3.5}$|, but the circumstellar dust contains large grains with a maximum size ≈ 1 µm. This result is consistent with a scenario in which HD 45677 is a young stellar object (≤ 108 yr), with the dust shell being a fossil of the molecular cloud left over from star formation.
Circumstellar dust
Spectral energy distribution
Extinction (optical mineralogy)
Cite
Citations (10)
In the early epoch of galaxy evolution, dust is only supplied by supernovae (SNe). With the aid of a new physical model of dust production by SNe developed by Nozawa et al. (2003) (N03), we constructed a model of dust emission from forming galaxies on the basis of the theoretical framework of Takeuchi et al. (2003) (T03). N03 showed that the produced dust species depends strongly on the mixing within SNe. We treated both unmixed and mixed cases and calculated the infrared (IR) spectral energy distribution (SED) of forming galaxies for both cases. Our model SED is less luminous than the SED of T03 model by a factor of 2-3. The difference is due to our improved treatment of UV photon absorption cross section, as well as different grain size and species newly adopted in this work. The SED for the unmixed case is found to have an enhanced near to mid-IR (N-MIR) continuum radiation in its early phase of the evolution (age < 10^{7.25} yr) compared with that for the mixed case. The strong N--MIR continuum is due to the emission from Si grains, which only exist in the species of the unmixed dust production. We also calculated the IR extinction curves for forming galaxies. Then we calculated the SED of a local starbursting dwarf galaxy SBS 0335-052. Our present model SED naturally reproduced the strong N--MIR continuum and the lack of cold FIR emission of SBS 0335-052. We found that only the SED of unmixed case can reproduce the NIR continuum of this galaxy. We then made a prediction for the SED of another typical star-forming dwarf, I Zw 18. We also presented the evolution of the SED of LBGs. Finally, we discussed the possibility of observing forming galaxies at z > 5.
Extinction (optical mineralogy)
Spectral energy distribution
Circumstellar dust
Cite
Citations (35)
Aims. By using the spectral energy distribution (SED) from the near-infrared to the radio of a statistically significant number of luminous infrared galaxies we determine important physical parameters for this population of objects. In particular we constrain the optical depth towards the luminosity source, the star formation rate, the star formation efficiency and the AGN fraction.
Spectral energy distribution
Energy distribution
Cite
Citations (85)
Aims.We aim to constrain new starburst/AGN models of IRAS bright galaxies via their spectral energy distribution from the near-infrared to the radio. To this end, we determine the radio spectra for a sample of 31 luminous and ultraluminous IRAS galaxies (LIRGs/ULIRGs).
Spectral energy distribution
Energy distribution
Cite
Citations (65)
Studies of astrophysical dust grains in circumstellar shells, the interstellar medium, and the solar system may provide information about stellar evolution and about physical conditions in the primitive solar nebula. The following subject areas are covered: (1) the cycling of dust in stellar evolution and the formation of planetary systems; (2) astrophysical dust grains in circumstellar environments; (3) circumstellar grain formation and mass loss; (4) interstellar dust grains; (5) comet dust and the zodiacal cloud; (6) the survival of dust grains during stellar evolution; and (7) establishing connections between stardust and dust in the solar system.
Circumstellar dust
Zodiacal light
Comet dust
Intergalactic dust
Dust lane
Dark nebula
Presolar grains
Cite
Citations (0)
The formation process of dust grains around cool stars and the dust processing in the interstellar space are reviewed. Infrared spectral characteristics of circumstellar dust grains indicate that newly-formed grains are not in a highly crystalline state, but they are rather amorphous material. The dust formation process in circumstellar regions must involve kinematic aspects to a large degree. On the other hand, theoretical investigations suggest that the destruction process of dust grains in the interstellar space is quite rapid compared to the supply rate from stellar sources. Therefore, a large fraction of dust grains must be forming also in the interstellar space. Very few investigations have been attemped on the formation of solid particles under the interstellar harsh conditions, but they will be essential in the study of interstellar dust.
Circumstellar dust
Interstellar ice
Dust lane
Intergalactic dust
Dark nebula
Cite
Citations (0)
We use the Expanded Very Large Array to image radio continuum emission from local luminous and ultraluminous infrared galaxies (LIRGs and ULIRGs) in 1 GHz windows centered at 4.7, 7.2, 29, and 36 GHz. This allows us to probe the integrated radio spectral energy distribution (SED) of the most energetic galaxies in the local universe. The 4–8 GHz flux densities agree well with previous measurements. They yield spectral indices α ≈ −0.67 (where Fν∝να) with ±0.15 (1σ) scatter, typical of nonthermal (synchrotron) emission from star-forming galaxies. The contrast of our 4–8 GHz data with literature 1.5 and 8.4 GHz flux densities gives further evidence for curvature of the radio SED of U/LIRGs. The SED appears flatter near ∼1 GHz than near ∼6 GHz, suggesting significant optical depth effects at lower frequencies. The high-frequency (28–37 GHz) flux densities are low compared to extrapolations from the 4–8 GHz data. We confirm and extend to higher frequency a previously observed deficit of high-frequency radio emission for luminous starburst galaxies.
Spectral energy distribution
Radio spectrum
Cite
Citations (32)