相关论文: Hot Gas, Cold Gas and Sub-Halos in a Lyman-alpha B…
The baryons inside high-redshift halos with virial temperatures above T=10^4 K cool radiatively as they condense inside dark matter potential wells. We show that the release of the gravitational binding energy, over the halo assembly…
We present observations of a peculiar Lyman alpha-emitting galaxy at redshift 3.344, discovered in a deep, blind spectroscopic survey for faint Lyman alpha emitters with the Magellan II telescope in the Hubble Ultra Deep Field (HUDF). The…
Motivated by recent observation of Lanzetta et al. that most luminous galaxies at low redshifts produce $\lya$ absorption at impact parameter $l\lsim 160 \kpch$, we propose that these absorbers are clouds confined by the pressure of ambient…
We present the results of an intermediate resolution (~2 angstrom) spectroscopy of a sample of 37 candidate Lyman alpha blobs and emitters at redshift z=3.1 using the DEIMOS spectrograph on the 10 m Keck telescope. The emission lines are…
Exploring the origin of Ly-alpha nebulae (blobs) requires measurements of their gas kinematics that are impossible with only the resonant, optically-thick LyA line. To define gas motions relative to the systemic velocity of the blob, the…
The most remarkable class of high-redshift objects observed so far is extended Ly$\alpha$ emission-line blobs found in an over-density region at redshift 3.1. They may be either a dust-enshrouded, extreme starburst galaxy with a large-scale…
We investigate a model for the high-ionization state gas associated with observed damped Lyman-alpha systems, based on a semi-analytic model of galaxy formation set within the paradigm of hierarchical structure formation. In our model, the…
We present deep optical spectroscopy of an extended Ly$\alpha$ emission-line blob located in an over-dense region at redshift $z \approx 3.1$; `blob 1' of Steidel et al. (2000). The origin of such Ly$\alpha$ blobs has been debated for some…
We report observations of Lyman Alpha Blob 1 (LAB1) in the SSA 22 protocluster region (z=3.09) with the integral-field spectrograph SAURON. We increased the signal-to-noise in the spectra by more than a factor three compared to our previous…
Spatially extended halos of H I Ly$\alpha$ emission are now ubiquitously found around high-redshift star-forming galaxies. But our understanding of the nature and powering mechanisms of these halos is still hampered by the complex radiative…
We present IRAM PdBI observations of the CO(3-2) and CO(5-4) line transitions from a Ly-alpha blob at z~2.7 in order to investigate the gas kinematics, determine the location of the dominant energy source, and study the physical conditions…
A hot gas halo is predicted by chemodynamical models during the early evolution of spheroidal galaxies. Cold condensations, arising from thermal instabilities in the hot gas, are expected to be embedded in the hot halo. In the early phases…
We report the detection at 850um of the central source in SSA22-LAB1, the archetypal Lyman-alpha Blob (LAB), a 100kpc-scale radio-quiet emission-line nebula at z=3.1. The flux density of the source, $S_{850}=4.6\pm1.1$mJy implies the…
We present spectroscopic measurements of the [OIII] emission line from two subregions of strong Lyman-alpha emission in a radio-quiet Lyman-alpha blob (LAB). The blob under study is LAB1 (Steidel et al. 2000) at z ~ 3.1, and the [OIII]…
This paper discusses infrared and millimetre-wavelength observations of a Lyman-alpha blob discovered by Smith & Jarvis, a candidate for ionization by the cold accretion scenario discussed in Fardal et al. and Dijkstra et al. We have…
The formation of the first galaxies is accompanied by large accretion flows and virialization shocks, during which the gas is shock-heated to temperatures of $\sim10^4$ K, leading to potentially strong fluxes in the Lyman alpha line.…
We investigate the physical state of HI absorbing gas at low redshift (z = 0.25) using a subset of cosmological, hydrodynamic simulations from the OWLS project, focusing in particular on broad (b_HI > 40 km/s) HI Lyman-Alpha absorbers…
We present the results of the observations of the Ly\alpha\ line profiles of 91 emission-line galaxies at z=3.1 with the spectral resolution of \lambda/\delta\lambda (FWHM) = 1700, or 180 km/s. A significant fraction, ~50% of the observed…
We report new HST COS and STIS spectroscopy of a star-forming region (~100 solar masses/year) in the center of the X-ray cluster RXJ1532.9+3021 (z=0.362), to follow-up the CLASH team discovery of luminous UV filaments and knots in the…
We propose a new model for the extended Ly alpha blobs found recently at high redshift z ~ 3. The observational properties of these blobs are; 1) the observed Ly alpha luminosities are ~ 10^{43} h^{-2} ergs s^{-1}, 2) they appear elongated…