High-Redshift Metals. I. The Decline of C IV at z > 5.3 (2009)
Becker, George D., Rauch, Michael, Sargent, Wallace L. W.
We present the results from our search for C iv absorption systems at redshifts z = 5.3-6.0. We have observed four z ~ 6 QSOs with Keck/NIRSPEC in echelle mode. The data are the most sensitive yet...
Understanding Single Tops using Jets (2009)
Plehn, Tilman, Rauch, Michael, Spannowsky, Michael
Top plus jets production at hadron collider allows us to study the couplings of the top quark. In the Standard Model, two single top processes contribute to the top-jets final state. Beyond the...
Measuring the Higgs Sector (2009)
Lafaye, Remi, Plehn, Tilman, Rauch, Michael, Zerwas, Dirk, Duehrssen, Michael
If we find a light Higgs boson at the LHC, there should be many observable channels which we can exploit to measure the relevant parameters in the Higgs sector. We use the SFitter framework to map...
Abstract Dynamic Adaptive Power Management For — And By — (2008)
Michael Rauch, A Java, Virtual Machine
Traditionally, adaptive power management has been performed at the operating system (OS) level. We present a dynamic adaptive power-management plugin for the Java Virtual Machine (JVM) that improves...
High Redshift Metals I.: The Decline of C IV at z > 5.3 (2008)
Becker, George D., Rauch, Michael, Sargent, Wallace L. W.
We present the results from our search for C IV in the intergalactic medium at redshifts z=5.3-6.0. We have observed four z~6 QSOs with Keck/NIRSPEC in echelle mode. The data are the most sensitive...
Rauch, Michael, Haehnelt, Martin, Bunker, Andrew, Becker, George, Marleau, Francine, Graham, James, ...
We have conducted a long-slit search for low surface brightness Lyα emitters at redshift 2.67 < z < 3.75. A 92 hr long exposure with the ESO VLT FORS2 instrument down to a 1σ surface brightness...
Quantum Effects in Higgs-Boson Production Processes at Hadron Colliders (2008)
The search for Higgs bosons and extensions of the Standard Model of Elementary Particle Physics are main tasks of the Large Hadron Collider (LHC) at CERN which will start operation mid-2008. In this...
Quantum Effects in Higgs-Boson Production Processes at Hadron Colliders (2008)
The search for Higgs bosons and extensions of the Standard Model of Elementary Particle Physics are main tasks of the Large Hadron Collider (LHC) at CERN which will start operation mid-2008. In this...
Viel, Matteo, Becker, George D., Bolton, James S., Haehnelt, Martin G., Rauch, Michael, Sargent, Wallace L.
We present constraints on the mass of warm dark matter (WDM) particles derived from the Lyman-alpha flux power spectrum of 55 high-resolution HIRES spectra at 2.0~5.6 keV (2sigma) for sterile...
Absorbers At High Redshift --- Large Disks Or Galactic Building Blocks? (2008)
Martin Haehnelt, Matthias Steinmetz, Michael Rauch
We investigate the nature of the physical structures giving rise to damped Lyff absorption systems (DLAS) at high redshift. In particular, we examine the suggestion that rapidly rotating large disks...
Viel, Matteo, Becker, George D., Bolton, James S., Haehnelt, Martin G., Rauch, Michael, Sargent, Wallace L. W.
CIV Absorption From Galaxies in the Process of Formation (2007)
Martin Haehnelt, Matthias Steinmetz, Michael Rauch
We investigate the heavy element QSO absorption systems caused by gas condensations at high redshift which evolve into galaxies at the present epoch. Artificial QSO spectra were generated for a...
The metal line systems in HS1700+6416: Evidence for inhomogeneities (2007)
Patrick Petitjean Rudiger, Patrick Petitjean, Rudiger Riediger, Michael Rauch
. We present a high S/N ratio optical spectrum of the bright quasar HS 1700+6416. These data usefully complement the UV HST data from Vogel & Reimers (1995). We analyse the metal line systems...
Martin G. Haehnelt, Michael Rauch, Hubble Fellow
Estimates of the linear extent of heavy-element absorption systems along the line-of-sight to a QSO often assume that the cloud is photoionized and that the temperature takes the equilibrium value...
Michael Rauch, Martin G. Haehnelt, Matthias Steinmetz
In a hierarchical cosmogony galaxies build up by continuous merging of smaller structures. At redshift three the matter content of a typical present-day galaxy is dispersed over several individual...
Rauch, Michael, Haehnelt, Martin, Bunker, Andrew, Becker, George, Marleau, Francine, Graham, James, ...
We have conducted a long slit search for low surface brightness Lyman-alpha emitters at redshift 2.67 < z < 3.75. A 92 hour long exposure with VLT/FORS2 down to a 1-sigma surface brightness detection...
Measuring Supersymmetry (2007)
Lafaye, Remi, Plehn, Tilman, Rauch, Michael, Zerwas, Dirk
If new physics is found at the LHC (and the ILC) the reconstruction of the underlying theory should not be biased by assumptions about high--scale models. For the mapping of many measurements onto...
Quantum Effects in Higgs-Boson Production Processes at Hadron Colliders (2007)
The search for Higgs bosons and extensions of the Standard Model of Elementary Particle Physics are main tasks of the Large Hadron Collider (LHC) at CERN which will start operation mid-2007. In this...
The Evolution of Optical Depth in the Lyα Forest: Evidence Against Reionization at z~6 (2007)
Becker, George D., Rauch, Michael, Sargent, Wallace L. W.
We examine the evolution of the IGM Lyα optical depth distribution using the transmitted flux probability distribution function (PDF) in a high-resolution sample of 55 QSOs spanning absorption...
Galactic Wind Signatures around High Redshift Galaxies (2007)
Kawata, Daisuke, Rauch, Michael
We carry out cosmological chemodynamical simulations with different strengths of supernova (SN) feedback and study how galactic winds from star-forming galaxies affect the features of hydrogen (HI)...
Higgs-Boson Production in Association with Heavy Quarks (2007)
Hollik, Wolfgang, Rauch, Michael
Associated production of a Higgs boson with a heavy, i.e. top or bottom, quark-anti-quark pair provide observation channels for Higgs bosons at the LHC which can be used to measure the respective...
Galactic wind signatures around high-redshift galaxies (2007)
Kawata, Daisuke, Rauch, Michael
We carry out cosmological chemodynamical simulations with different strengths of supernova (SN) feedback and study how galactic winds from star-forming galaxies affect the features of hydrogen (Hi)...
Galactic wind signatures around high-redshift galaxies (2007)
Kawata, Daisuke, Rauch, Michael
We carry out cosmological chemodynamical simulations with different strengths of supernova (SN) feedback and study how galactic winds from star-forming galaxies affect the features of hydrogen (Hi)...
Higgs-Boson Production in Association with Heavy Quarks (2006)
Hollik, Wolfgang, Rauch, Michael
Associated production of a Higgs boson with a heavy, i.e. top or bottom, quark-anti-quark pair provide observation channels for Higgs bosons at the LHC which can be used to measure the respective...
The Evolution of Optical Depth in the Ly-alpha Forest: Evidence Against Reionization at z~6 (2006)
Becker, George D., Rauch, Michael, Sargent, Wallace L. W.
We examine the evolution of the IGM Ly-alpha optical depth distribution using the transmitted flux probability distribution function (PDF) in a sample of 63 QSOs spanning absorption redshifts 1.7 < z...
Discovery of excess O I absorption towards the z = 6.42 QSO SDSS J1148+5251 (2005)
Becker, George D., Sargent, Wallace L. W., Rauch, Michael, Simcoe, Robert A.
We present a search for O I in the spectra of nine 4.9 < z_qso < 6.4 QSOs taken with Keck/HIRES. We detect six systems with N(O I) > 10^13.7 cm^{-2} in the redshift intervals where O I 1302 falls...
Expansion and Collapse in the Cosmic Web (2005)
Rauch, Michael, Becker, George D., Viel, Matteo, Sargent, Wallace L. W., Smette, Alain, Simcoe, Robert A., ...
We study the kinematics of the gaseous cosmic web at high redshift with Lyman alpha forest absorption in multiple QSO sightlines. Using a simple analytic model and a cosmological hydrodynamic...
Simcoe, Robert A., Sargent, Wallace L. W., Rauch, Michael, Becker, George D.
We present a study of galaxies and intergalactic gas toward the z=2.73 quasar HS1700+6416, to explore the effects of galaxy formation feedback on the IGM. Our observations and ionization simulations...
The Quartic Higgs Coupling at Hadron Colliders (2005)
The quartic Higgs self-coupling is the final measurement in the Higgs potential needed to fully understand electroweak symmetry breaking. None of the present or future colliders are known to be able...
Lidz, Adam, Heitmann, Katrin, Hui, Lam, Habib, Salman, Rauch, Michael, Sargent, Wallace L. W.
The analysis of the Lyman-alpha forest of absorption lines in quasar spectra has emerged as a potentially powerful technique to constrain the linear matter power spectrum. In most previous work, the...
The Quartic Higgs Coupling at Hadron Colliders (2005)
The quartic Higgs self-coupling is the final measurement in the Higgs potential needed to fully understand electroweak symmetry breaking. None of the present or future colliders are known to be able...
Abundance Profiles and Kinematics of Damped Lyman-alpha Absorbing Galaxies at z < 0.65 (2004)
Chen, Hsiao-Wen, Kennicutt Jr, Robert C., Rauch, Michael
We present a spectroscopic study of six damped Lya absorption (DLA) systems at z 10^{11} h^{-1} M_sun appear to be common at intermediate redshifts. (3) Using an ensemble of six galaxy-DLA pairs, we...
Simcoe, Robert A., Sargent, Wallace L. W., Rauch, Michael
We present a direct measurement of the metallicity distribution function for the high redshift intergalactic medium. We determine the shape of this function using survival statistics, which account...
Metallicity of the intergalactic medium using pixel statistics: III. Silicon (2003)
Aguirre, Anthony, Schaye, Joop, Kim, Tae-Sun, Theuns, Tom, Rauch, Michael, Sargent, Wallace L. W.
(Modified) We study the abundance of silicon in the intergalactic medium by analyzing the statistics of SiIV, CIV, and HI pixel optical depths in a sample of 19 high-quality quasar absorption spectra...
Schaye, Joop, Aguirre, Anthony, Kim, Tae-Sun, Theuns, Tom, Rauch, Michael, Sargent, Wallace L. W.
(Modified) We measure the distribution of carbon in the intergalactic medium as a function of redshift z and overdensity delta. Using a hydrodynamical simulation to link the H I absorption to the...
Complete 1-Loop Calculation of the T-violating D-Parameter in Neutron Decay in the MSSM (2003)
We investigate the violation of time reversal invariance in the decay of the free neutron in the framework of the Minimal Supersymmetric Standard Model (MSSM). The coefficient of the triple product...
Complete 1-Loop Calculation of the T-violating D-Parameter in Neutron Decay in the MSSM (2003)
We investigate the violation of time reversal invariance in the decay of the free neutron in the framework of the Minimal Supersymmetric Standard Model (MSSM). The coefficient of the triple product...
Complete 1-Loop Calculation of the T-violating D-Parameter in Neutron Decay in the MSSM (2003)
We investigate the violation of time reversal invariance in the decay of the free neutron in the framework of the Minimal Supersymmetric Standard Model (MSSM). The coefficient of the triple product...
Simcoe, Robert A., Sargent, Wallace L. W., Rauch, Michael
We describe a survey for OVI absorption in the spectra of 5 high redshift quasars (2.2 < z < 2.8). We identify 12 cosmological systems, and 6 systems that are either ejected from the background QSO...
The Impact of Galaxies on their Environment from Observations of Gravitationally lensed QSOs (2001)
Observations of absorption systems in close, multiple lines of sight to gravitationally lensed QSOs can be used to infer the density fluctuations and motions of the gas clouds giving rise to the...
Rauch, Michael, Sargent, Wallace L. W., Barlow, Thomas A., Carswell, Robert F.
Spectra from the Keck HIRES instrument of the Lyman alpha forests in the lines of sight to the A and C components of the gravitationally lensed QSO Q1422+231 were used to investigate the structure of...
Small Scale Structure at High Redshift: II. Physical Properties of the CIV Absorbing Clouds (2001)
Rauch, Michael, Sargent, Wallace L. W., Barlow, Thomas A.
Keck HIRES spectra were obtained of the separate images of three gravitationally lensed QSOs (UM 673, Q1104-1804, and Q1422+2309). We studied the velocity and column density differences in CIV...
The detection of oxygen in the low-density intergalactic medium (2000)
Schaye, Joop, Rauch, Michael, Sargent, Wallace L. W., Kim, Tae-Sun
The abundances of metals in the intergalactic medium (IGM) can be used to constrain the amount of star formation at high redshift and the spectral shape of the ionizing background radiation. For both...
McDonald, Patrick, Miralda-Escude, Jordi, Rauch, Michael, Sargent, Wallace L. W., Barlow, Tom A., Cen, Renyue
The evolution of the temperature in the intergalactic medium is related to the reionization of hydrogen and helium, and has important consequences for our understanding of the Lya forest and of...
Constraining reionization using the thermal history of the baryons (2000)
Schaye, Joop, Theuns, Tom, Rauch, Michael, Efstathiou, George, Sargent, Wallace L. W.
The thermal evolution of the intergalactic medium (IGM) depends on the reionization history of the universe. Numerical simulations indicate that the low density IGM, which is responsible for the low...
The thermal history of the intergalactic medium (1999)
Schaye, Joop, Theuns, Tom, Rauch, Michael, Efstathiou, George, Sargent, Wallace L. W.
At redshifts z >~ 2, most of the baryons reside in the smooth intergalactic medium which is responsible for the low column density Lyman-alpha forest. This photoheated gas follows a tight...
Haehnelt, Martin G., Steinmetz, Matthias, Rauch, Michael
We combine predictions for several hierarchical cosmogonies with observational evidence on damped Lyman alpha systems to establish a correspondence between the high redshift galaxy population and the...
McDonald, Patrick, Miralda-Escude, Jordi, Rauch, Michael, Sargent, Wallace L. W., Barlow, Tom A., Cen, Renyue, ...
A sample of eight quasars observed at high resolution and signal-to-noise is used to determine the probability distribution function (PDF), the power spectrum, and the correlation function of the...
KECK HIRES Spectroscopy of APM 08279+5255 (1999)
Ellison, Sara L., Lewis, Geraint F., Pettini, Max, Sargent, Wallace L. W., Chaffee, Frederic H., Foltz, Craig B., ...
With an optical R-band magnitude of 15.2, the recently discovered z=3.911 BAL quasar APM 08279+5255 is an exceptionally bright high redshift source. Its brightness has allowed us to acquire a high...
Glimpses of the Interstellar Medium at Redshift 3.5 (1998)
Rauch, Michael, Sargent, Wallace L. W., Barlow, Thomas A.
We have obtained high resolution (FWHM = 4.4 km/s) Keck spectra of images A and C of the gravitationally lensed QSO Q1422+231. The images are separated by 1.3" on the sky. In an absorption system at...
Boksenberg, Alec, Sargent, Wallace L. W., Rauch, Michael
An extremely careful separation of the weak metal-line systems relating to the Lyman forest absorbers into individual ``single-phase ionization'' components with accurate parameters has yielded a...
The Lyman Alpha Forest in the Spectra of QSOs (1998)
Observations of redshifted Lyman alpha forest absorption in the spectra of quasistellar objects (QSOs) provide a highly sensitive probe of the distribution of gaseous matter in the universe. Over the...
Lopez, Sebastian, Reimers, Dieter, Rauch, Michael, Sargent, Wallace L. W., Smette, Alain
Using new HST/FOS, NTT/EMMI, and Keck/HIRES spectra of the gravitationally-lensed double QSO HE 1104-1805 AB (z=2.31, \theta=3.2), and assuming UV photoionization by a metagalactic radiation field,...
Lu, Limin, Sargent, Wallace L. W., Barlow, Thomas A., Rauch, Michael
We investigate the metal contents of Lyman-alpha clouds at 2.2
Small Scale Structure in the Universe and the Distribution of Baryons at High Redshift (1997)
We briefly discuss the relevance of Lyman alpha forest observations for measuring cosmological parameters, comparing the properties of high z QSO spectra with those of artifical spectra from...
Damped Lyman alpha absorbers at high redshift -- large disks or galactic building blocks? (1997)
Haehnelt, Martin G., Steinmetz, Matthias, Rauch, Michael
We investigate the nature of the physical structures giving rise to damped Lyman alpha absorption systems (DLAS) at high redshift. In particular, we examine the suggestion that rapidly rotating large...
Rauch, Michael, Haehnelt, Martin G., Steinmetz, Matthias
In hierarchical cosmogonies at redshift three the matter content of a typical present-day galaxy is dispersed over several individual clumps embedded in sheet-like structures, often aligned along...
Non-equilibrium effects on line-of-sight size estimates of QSO absorption systems (1996)
Haehnelt, Martin G., Rauch, Michael, Steinmetz, Matthias
Estimates of the linear extent of heavy-element absorption systems along the line-of-sight to a QSO often assume that the cloud is photoionized and that the temperature takes the equilibrium value...
CIV Absorption From Galaxies in the Process of Formation (1995)
Haehnelt, Martin, Steinmetz, Matthias, Rauch, Michael
We investigate the heavy element QSO absorption systems caused by gas condensations at high redshift which evolve into galaxies with circular velocity of 100 to 200 km/s at the present epoch....
We discuss the effects of gravitational collapse on the shape of absorption line profiles for low column density (log N(HI) < 14) Lyman Alpha forest clouds and argue by comparison with cosmological...
The Lyman Alpha Forest from Gravitational Collapse in the CDM+Lambda Model (1995)
Miralda-Escude, Jordi, Cen, Renyue, Ostriker, Jeremiah P., Rauch, Michael
We model the $\lya$ forest in a spatially flat, CDM model with $\Omega=0.4$, with an Eulerian hydrodynamic simulation, and find that the intergalactic, photoionized gas collapses into sheet-like and...
The metal line systems in HS1700+6416: Evidence for inhomogeneities (1995)
Petitjean, Patrick, Riediger, Ruediger, Rauch, Michael
We present a high S/N ratio optical spectrum of the bright quasar HS1700+6416. These data usefully complement the UV HST data from Vogel and Reimers (1995). We analyse the metal line systems using...
The Distribution of Column Densities and b Values in the Lyman-Alpha Forest (1995)
Hu, Esther M., Kim, Tae-Sun, Cowie, Lennox L., Songaila, Antoinette, Rauch, Michael
We describe the properties of the Ly$\alpha$ forest in the column density range $\nhi \geq 2\times10^{12}$ cm$^{-2}$ based on 1056 lines in the wavelength range 4300--5100\AA measured in extremely...
Omega_baryon and the Geometry of Intermediate Redshift Lyman alpha Absorption Systems (1995)
Rauch, Michael, Haehnelt, Martin G.
Estimates of Omega_baryon from primordial nucleosynthesis together with standard assumptions about the ionization state of low column density Lyman alpha forest clouds can be used to determine an...
Gravitational Collapse of Small-Scale Structure as the Origin of the Lyman Alpha Forest (1994)
Cen, Renyue, Miralda-Escude, Jordi, Ostriker, Jeremiah P., Rauch, Michael
If gravitational clustering is a hierarchical process, the present large-scale structure of the galaxy distribution implies that structures on smaller scales must have formed at high redshift. We...
Lyman alpha absorption systems. (1992)
Thesis (Ph. D.)--University of Cambridge, 1992.
Harnwegsinfekte bei Diabetikern [microform] : eine retrospektive Erhebung / (1988)
Thesis (doctoral)--Westfälische Wilhelms-Universität, 1988.