This paper considers how the first subgalactic structures produced the UV radiation that ionized the intergalactic medium before z = 5, and the `feedback' effects of the UV radiation on...
High-Redshift Galaxies, Their Active Nuclei and Central Black Holes (2007)
Martin Haehnelt, Priyamvada Natarajan, Martin J. Rees
We demonstrate that the luminosity function of the recently detected population of actively star-forming galaxies at redshift three and the B-band QSO luminosity function at the same redshift can...
Massive Black Holes And Light Element Nucleosynthesis In A Baryonic Universe (e30475j) (2007)
Nickolay Gnedin, Jeremiah P. Ostriker, Martin J. Rees
We re-examine the model proposed by Gnedin and Ostriker (1992) in which Jeans' mass black holes (MBH ß 10 6 M fi ) form shortly after decoupling. There is no nonbaryonic dark matter in this...
The Radiative Feedback Of The First Cosmological Objects (2007)
Zolt' An, Zolt An Haiman, Tom Abel, Martin J. Rees
In hierarchical models of structure formation, an early cosmic UV background (UVB) is produced by the small (T vir ¸ ! 10 4 K) halos that collapse before reionization. The UVB at energies below...
Reionization of the Inhomogeneous Universe (2007)
Jordi Miralda-Escud'e, Martin J. Rees
A model of the density distribution in the intergalactic medium, motivated by that found in numerical simulations, is used to demonstrate the effect of a clumpy IGM and discrete sources on the...
Max Tegmark, Joseph Silk, Martin J. Rees, Alain Blanchard, Francesco Palla, Fohringer Ring, ...
The minimum mass that a virialized gas cloud must have in order to be able to cool in a Hubble time is computed, using a detailed treatment of the chemistry of molecular hydrogen. With a simple model...
Implications of very rapid TeV variability in blazars (2007)
Begelman, Mitchell C., Fabian, Andrew C., Rees, Martin J.
We discuss the implications of rapid (few-minute) variability in the TeV flux of blazars, which has been observed recently with the HESS and MAGIC telescopes. The variability timescales seen in PKS...
Pe'er, Asaf, Ryde, Felix, Mészáros, Peter, Rees, Martin J.
In recent years increasing evidence has emerged for a thermal component in the gamma- and X-ray spectrum of the prompt emission phase in gamma-ray bursts. The temperature and flux of the thermal...
Massive Black Holes: formation and evolution (2007)
Rees, Martin J., Volonteri, Marta
Supermassive black holes are nowadays believed to reside in most local galaxies. Observations have revealed us vast information on the population of local and distant black holes, but the detailed...
Pe'er, Asaf, Mészáros, Peter, Rees, Martin J.
Observations of early afterglow emission from gamma-ray bursts (GRB's) with the Swift satellite show steep decay of the X-ray light curve, F_\nu(t) ~ t^{-\alpha} with \alpha ~ 2.5 - 4 at ~300-500 s...
Formation of Supermassive Black Holes by Direct Collapse in Pregalactic Halos (2006)
Begelman, Mitchell C., Volonteri, Marta, Rees, Martin J.
We describe a mechanism by which supermassive black holes can form directly in the nuclei of protogalaxies, without the need for seed black holes left over from early star formation. Self-gravitating...
Neutron-loaded outflows in gamma-ray bursts (2005)
Rossi, Elena M., Beloborodov, Andrei M., Rees, Martin J.
Relativistic neutron-loaded outflows in gamma-ray bursts are studied at their early stages, before deceleration by a surrounding medium. The outflow has four components: radiation, electrons, protons...
Dimensionless constants, cosmology and other dark matters (2005)
Tegmark, Max, Aguirre, Anthony, Rees, Martin J, Wilczek, Frank
We identify 31 dimensionless physical constants required by particle physics and cosmology, and emphasize that both microphysical constraints and selection effects might help elucidate their origin....
Haehnelt, Martin G., Davies, Melvyn B., Rees, Martin J.
Attempts of Magain et al (2005) to detect the host galaxy of the bright QSO HE0450--2958 have not been successful. We suggest that the supermassive black hole powering the QSO was ejected from the...
Pe'er, Asaf, Mészáros, Peter, Rees, Martin J.
A thermal radiative component is likely to accompany the first stages of the prompt emission of Gamma-ray bursts (GRB's) and X-ray flashes (XRF's). We analyze the effect of such a component on the...
Rapid growth of high redshift black holes (2005)
Volonteri, Marta, Rees, Martin J.
We discuss a model for the early assembly of supermassive black holes (SMBHs) at the center of galaxies that trace their hierarchical build-up far up in the dark halo `merger tree'. Motivated by the...
Peak energy clustering and efficiency in compact objects (2005)
Pe'er, Asaf, Mészáros, Peter, Rees, Martin J.
We study the properties of plasmas containing a low energy thermal photon component at comoving temperature \theta \equiv kT'/m_e c^2 \sim 10^{-5} - 10^{-2} interacting with an energetic electron...
Cyclotron Maser Emission from Blazar Jets? (2005)
Begelman, Mitchell C., Ergun, Robert E., Rees, Martin J.
We consider the production of electron cyclotron maser emission by low-density, highly magnetized plasmas in relativistic jets. The population inversion required to drive cyclotron maser instability...
Have we detected one of the sources responsible for an early reionisation of the Universe? (2004)
Ricotti, Massimo, Haehnelt, Martin G., Pettini, Max, Rees, Martin J.
In a recent paper Pell'o et al. have reported a candidate z=10 galaxy, A1835#1916, which was found in a near-infrared survey of the central regions of the gravitational lensing cluster A1835. If this...
Dark Matter: Introduction (2004)
This short review was prepared as an introduction to the Royal Society's 'Dark Matter' conference. It addresses the embarrassing fact that 95% of the universe is unaccounted for. Favoured dark matter...
Yuan, Ye-Fei, Narayan, Ramesh, Rees, Martin J.
The existence of black holes remains open to doubt until other conceivable options are excluded. With this motivation, we consider a model of a compact star in which most of the mass consists of dark...
Numerical coincidences and 'tuning' in cosmology (2004)
Fred Hoyle famously drew attention to the significance of apparent coincidences in the energy levels of the carbon and oxygen nucleus. This paper addresses the possible implications of other...
Black holes in the real universe and their prospects as probes of relativistic gravity (2004)
Collapsed objects have definitely been observed: some are stellar-mass objects, the endpoint of massive stars; others, millions of times more massive, have been discovered in the cores of most...
Heating and deceleration of GRB fireballs by neutron decay (2004)
Rossi, Elena M., Beloborodov, Andrei M., Rees, Martin J.
Fireballs with high energy per baryon rest mass (> 400) contain a relatively slow neutron component. We show here that in this situation the thermal history of fireballs is very different from the...
Early reionization by miniquasars (2003)
Madau, Piero, Rees, Martin J., Volonteri, Marta, Haardt, Francesco, Oh, S. Peng
Motivated by the recent detection by WMAP of a large optical depth to Thomson scattering -- implying a very early reionization epoch -- we assess a scenario where the universe was reionized by...
Compton drag as a mechanism for very high linear polarization in Gamma-Ray Bursts (2003)
Lazzati, Davide, Rossi, Elena, Ghisellini, Gabriele, Rees, Martin J.
The recent claim by Coburn & Boggs to have detected a very high degree of linear polarization in the prompt emission of GRB 021206 has stimulated interest in how much polarization could arise in...
Photoionization Feedback in Low--Mass Galaxies at High Redshift (2003)
Dijkstra, Mark, Haiman, Zoltan, Rees, Martin J., Weinberg, David H.
The cosmic ultraviolet (UV) ionizing background impacts the formation of dwarf galaxies in the low-redshift universe (z=3) by suppressing gas infall into galactic halos with circular velocities up to...
Events in the life of a cocoon surrounding a light, collapsar jet (2002)
Ramirez-Ruiz, Enrico, Celotti, Annalisa, Rees, Martin J.
According to the collapsar model, gamma-ray bursts are thought to be produced in shocks that occur after the relativistic jet has broken free from the stellar envelope. If the mass density of the...
Gamma-Ray Burst Afterglow emission with a decaying magnetic field (2002)
In models for gamma ray burst afterglows, it is normally assumed that the external shock strongly amplifies the magnetic field and that this field maintains a steady value throughout the shocked...
Soft X-ray emission lines in the early afterglow of gamma-ray bursts (2002)
Lazzati, Davide, Ramirez-Ruiz, Enrico, Rees, Martin J.
We compute the luminosity of K_alpha emission lines produced by astrophysically abundant elements in the soft X-ray spectra of the early afterglow of gamma-ray bursts. We find that the detection of...
Feeding black holes at galactic centres by capture from isothermal cusps (2001)
Zhao, HongSheng, Haehnelt, Martin G., Rees, Martin J.
We estimate the rate at which stars are captured by supermassive black holes (BHs) in the centres of bulges and elliptical galaxies assuming that these initially had an isothermal cusp (rho ~ r^{-2}...
Di Matteo, Tiziana, Perna, Rosalba, Abel, Tom, Rees, Martin J.
Absorption or emission against the cosmic microwave background radiation (CMB) may be observed in the redshifted 21cm line if the spin temperature of the neutral intergalactic medium prior to...
Do globular clusters time the Universe? (2001)
Gnedin, Oleg Y., Lahav, Ofer, Rees, Martin J.
Estimating the age of the Universe is an old problem. Rapid progress in observational cosmology in recent years has led to more accurate values of the fundamental parameters. The current most popular...
Piecing together the big picture (2001)
This article (which appeared with illustrations) was the astrophysics/cosmology contribution to the historical series ``Pathways of Discovery'' which appeared in ``Science'' during last year.
Why AGN Studies Need Higher Resolution (2001)
The need for high angular resolution is emphasised, especially in the context of programs to understand massive black holes and the processes in their environment.
This contribution to the concluding session at IAU Symposium 205 offered comments on some current controversies, including the scientific status of the ''multiverse'' concept and on the prospects for...
Massive Black Holes as Population III Remnants (2001)
Recent numerical simulations of the fragmentation of primordial molecular clouds in hierarchical cosmogonies have suggested that the very first stars (the so-called Population III) may have been...
Extended Lyman Alpha Emission Around Young Quasars: a Constraint on Galaxy Formation (2001)
Haiman, Zoltan, Rees, Martin J.
The early stage in the formation of a galaxy inevitably involves a spatially extended distribution of infalling, cold gas. If a central luminous quasar turned on during this phase, it would result in...
Quiescent times in gamma-ray bursts: II. Dormant periods in the central engine? (2000)
Ramirez-Ruiz, Enrico, Merloni, Andrea, Rees, Martin J.
Within the framework of the internal-external shocks model for gamma-ray bursts, we study the various mechanisms that can give rise to quiescent times in the observed gamma-ray light-curves. In...
Early Metal Enrichment of the Intergalactic Medium by Pregalactic Outflows (2000)
Madau, Piero, Ferrara, Andrea, Rees, Martin J.
We assess supernova (SN)-driven pregalactic outflows as a mechanism for distributing the product of stellar nucleosynthesis over large cosmological volumes prior to the reionization epoch. SN ejecta...
HeII Recombination Lines From the First Luminous Objects (2000)
Oh, S. Peng, Haiman, Zoltan, Rees, Martin J.
The hardness of the ionizing continuum from the first sources of UV radiation plays a crucial role in the reionization of the intergalactic medium (IGM). While usual stellar populations have soft...
The Earliest Luminous Sources and the Damping Wing of the Gunn-Peterson Trough (2000)
Recent observations of high-redshift galaxies and quasars indicate that the hydrogen component of the intergalactic medium (IGM) must have been reionized at some redshift z>6. Prior to complete...
This brief introduction to the NATO ASI offers comments on current controversies, on the limits and prospects of cosmology in the coming decade, and on how the `sociology' of our subject may change...
`First Light' in the Universe; What Ended the "Dark Age"? (1999)
The universe would have been completely dark between the epoch of recombination and the development of the first non-linear structure. But at redshifts beyond 5 -- perhaps even beyond 20 -- stars...
The existence of supermassive collapsed objects in the cores of most galaxies poses still-unanswered questions. First, how did they form, and how does their mass depend on the properties of the host...
Compton Echoes from Gamma-ray Bursts (1999)
Madau, Piero, Blandford, Roger D., Rees, Martin J.
Recent observations of gamma-ray bursts (GRBs) have provided growing evidence for collimated outflows and emission, and strengthened the connection between GRBs and supernovae. If massive stars are...
Compton Dragged Gamma--Ray Bursts associated with Supernovae (1999)
Lazzati, Davide, Ghisellini, Gabriele, Celotti, Annalisa, Rees, Martin J.
It is proposed that the gamma-ray photons that characterize the prompt emission of Gamma-Ray Bursts are produced through the Compton drag process, caused by the interaction of a relativistic fireball...
The First Light seen in the redshifted 21-cm radiation (1999)
Tozzi, Paolo, Madau, Piero, Meiksin, Avery, Rees, Martin J.
We show how the investigation of the redshifted 21-cm radiation can give insight into the development of structures in the early universe (at redshifts z>5). In particular we investigate: the epoch...
The Radiative Feedback of the First Cosmological Objects (1999)
Haiman, Zoltan, Abel, Tom, Rees, Martin J.
In hierarchical models of structure formation, an early cosmic UV background (UVB) is produced by the small (T_vir < 10^4 K) halos that collapse before reionization. The UVB at energies below 13.6eV...
Radio Signatures of HI at High Redshift: Mapping the End of the ``Dark Ages'' (1999)
Tozzi, Paolo, Madau, Piero, Meiksin, Avery, Rees, Martin J.
The emission of 21-cm radiation from a neutral intergalactic medium (IGM) at high redshift is discussed in connection with the thermal and ionization history of the universe. The physical mechanisms...
The Distribution of Supermassive Black Holes in the Nuclei of Nearby Galaxies (1999)
Andrea Cattaneo, Martin G. Haehnelt, Martin J. Rees
The growth of supermassive black holes by merging and accretion in hierarchical models of galaxy formation is studied by means of Monte Carlo simulations. A tight linear relation between masses of...
Reionization of the Inhomogeneous Universe (1998)
Miralda-Escude, Jordi, Haehnelt, Martin, Rees, Martin J.
A model of the density distribution in the intergalactic medium, motivated by that found in numerical simulations, is used to demonstrate the effect of a clumpy IGM and discrete sources on the...
Radiative Transfer in a Clumpy Universe: III. The Nature of Cosmological Ionizing Sources (1998)
Madau, Piero, Haardt, Francesco, Rees, Martin J.
The history of the transition from a neutral intergalactic medium (IGM) to one that is almost fully ionized can reveal the character of cosmological ionizing sources. We study the evolution of the...
Probing the `Dark Age' with NGST (1998)
At redshifts between 5 and 20, stars and `subgalaxies' created the first heavy elements; these same systems (together perhaps with `miniquasars') generated the UV radiation that ionized the IGM, and...
The Large-Scale Smoothness of the Universe (1998)
Wu, Kelvin K. S., Lahav, Ofer, Rees, Martin J.
New measurements of galaxy clustering and background radiations provide improved constraints on the isotropy and homogeneity of the Universe on large scales. In particular, the angular distribution...
Quasars and Galaxy Formation (1998)
The formation of massive black holes may precede the epoch that characterises the peak of galaxy formation, as characterized by the star formation history in luminous galaxies. Hence protogalactic...
High-redshift galaxies, their active nuclei and central black holes (1997)
Haehnelt, Martin G., Natarajan, Priyamvada, Rees, Martin J.
We demonstrate that the luminosity function of the recently detected population of star-forming galaxies and the QSO luminosity function at z=3 can be matched with the mass function of dark matter...
Miralda-Escude, Jordi, Rees, Martin J.
If the universe was reionized by O and B stars in an early population of galaxies, the associated supernovae should have enriched the universe to a mean metallicity $\bar Z = 10^{-5} (1+ n_{rec})$,...
Shocked by GRB 970228: the afterglow of a cosmological fireball (1997)
Rees, Martin J., Meszaros, Peter
The location accuracy of the BeppoSAX Wide Field Cameras and acute ground-based followup have led to the detection of a decaying afterglow in X rays and optical light following the classical...
Gamma-ray bursts: Challenges to relativistic astrophysics (1997)
Although they were discovered more than 25 years ago, gamma-ray bursts are still a mystery. Even their characteristic distance is highly uncertain. All that we can be confident about is that they...
Astrophysical Evidence for Black Holes (1997)
The case for collapsed objects in some X-ray binary systems continues to strengthen. But there is now even firmer evidence for supermassive black holes in galactic centres. Gravitational collapse...
Miralda-Escude, Jordi, Rees, Martin J.
Recent evidence on the metal content of the high-redshift Lyman alpha forest seen in quasar spectra suggests that an early generation of galaxies enriched the intergalactic medium (IGM) at z ~ 5. We...
The Universe at $Z > 5$: when and how did the `Dark Age' End? (1996)
This paper considers how the first subgalactic structures produced the UV radiation that ionized the intergalactic medium before $z = 5$, and the `feedback' effects of the UV radiation on structure...
21-cm Tomography of the Intergalactic Medium at High Redshift (1996)
Madau, Piero, Meiksin, Avery, Rees, Martin J.
We investigate the 21-cm signature that may arise from the intergalactic medium (IGM) prior to the epoch of full reionization (z>5). In scenarios in which the IGM is reionized by discrete sources of...
Nucleosynthesis Constraints on Defect-Mediated Electroweak Baryogenesis (1995)
Brandenberger, Robert, Davis, Anne-Christine, Rees, Martin J.
In the defect-mediated electroweak baryogenesis scenario, baryons are produced in well separated regions of space. It is shown that between the electroweak phase transition at a temperature of $T...
Gamma-Ray Bursts from Blast Waves Around Galactic Nuetron Stars (1993)
Begelman, Mitchell C., Meszaros, P., Rees, Martin J.
If gamma-ray bursts originate in our Galaxy, they probably involve violent disturbances in the magnetospheres of neutron stars. Any event of this kind is likely to trigger the sudden expulsion of...
The universe at z > 5: When and how did the “dark age” end?
This paper considers how the first subgalactic structures produced the UV radiation that ionized the intergalactic medium before z = 5 and the “feedback” effects of the UV radiation on structure...
The universe at z > 5: When and how did the “dark age” end?
This paper considers how the first subgalactic structures produced the UV radiation that ionized the intergalactic medium before z = 5 and the “feedback” effects of the UV radiation on structure...
Cosmology: evidence for a ?big bang?
During the last 25 years, evidence has accumulated that our universe has evolved, over a period of 10 mix of matter and radiation, nor why it is expanding in the observed fashion, without further...