Skip to main content

Research Repository

Advanced Search

Professor JAMES BOLTON's Outputs (85)

Gas around galaxy haloes - II: hydrogen absorption signatures from the environments of galaxies at redshifts 2<z<3 (2015)
Journal Article
Tittley, E. R., Meiksin, A., Bolton, J. S., & Tittley, E. (2015). Gas around galaxy haloes - II: hydrogen absorption signatures from the environments of galaxies at redshifts 2

We compare predictions of large-scale cosmological hydrodynamical simulations for neutral hydrogen absorption signatures in the vicinity of 1011–1012.5 M⊙ haloes with observational measurements. Two different hydrodynamical techniques and a variety o... Read More about Gas around galaxy haloes - II: hydrogen absorption signatures from the environments of galaxies at redshifts 2<z<3.

Simulating the 21cm forest detectable with LOFAR and SKA in the spectra of high-zGRBs (2015)
Journal Article
Schaye, J., Jelić, V., Bolton, J. S., Ciardi, B., Inoue, S., Abdalla, F. B., Asad, K., Bernardi, G., Bolton, J. S., Brentjens, M., de Bruyn, A. G., Chapman, E., Daiboo, S., Fernandez, E. R., Ghosh, A., Graziani, L., Harker, G. J. A., Iliev, I. T., Jelic, V., Jensen, H., …Zaroubi, S. (2015). Simulating the 21cm forest detectable with LOFAR and SKA in the spectra of high-zGRBs. Monthly Notices of the Royal Astronomical Society, 453(1), 101-105. https://doi.org/10.1093/mnras/stv1640

We investigate the feasibility of detecting 21 cm absorption features in the afterglow spectra of high redshift long Gamma Ray Bursts (GRBs). This is done employing simulations of cosmic reionization, together with estimates of the GRB radio afterglo... Read More about Simulating the 21cm forest detectable with LOFAR and SKA in the spectra of high-zGRBs.

Lyman α emitters gone missing: evidence for late reionization? (2015)
Journal Article
Choudhury, T. R., Puchwein, E., Haehnelt, M. G., & Bolton, J. S. (2015). Lyman α emitters gone missing: evidence for late reionization?. Monthly Notices of the Royal Astronomical Society, 452(1), 261-277. https://doi.org/10.1093/mnras/stv1250

We combine high resolution hydrodynamical simulations with an intermediate resolution, dark matter only simulation and an analytical model for the growth of ionized regions to estimate the large scale distribution and redshift evolution of the visibi... Read More about Lyman α emitters gone missing: evidence for late reionization?.

The photoheating of the intergalactic medium in synthesis models of the UV background (2015)
Journal Article
Puchwein, E., Bolton, J. S., Haehnelt, M. G., Madau, P., Becker, G. D., & Haardt, F. (2015). The photoheating of the intergalactic medium in synthesis models of the UV background. Monthly Notices of the Royal Astronomical Society, 450(4), 4081-4097. https://doi.org/10.1093/mnras/stv773

We compare cosmological hydrodynamical simulations combined with the homogeneous metagalactic UV background (UVB) of Haardt & Madau (2012) (HM2012) to observations of the Lyman-alpha forest that are sensitive to the thermal and ionization state of th... Read More about The photoheating of the intergalactic medium in synthesis models of the UV background.

IGM constraints from the SDSS-III/BOSS DR9 Lyα forest transmission probability distribution function (2015)
Journal Article
Lee, K. G., Lee, K.-G., Hennawi, J., Spergel, D. N., Weinberg, D. H., Hogg, D. W., Viel, M., Bolton, J. S., Bailey, S., Pieri, M. M., Carithers, W., Schlegel, D. J., Lundgren, B., Palanque-Delabrouille, N., Suzuki, N., Schneider, D. P., & Yeche, C. (2015). IGM constraints from the SDSS-III/BOSS DR9 Lyα forest transmission probability distribution function. Astrophysical Journal, 799(2), 196. https://doi.org/10.1088/0004-637X/799/2/196

© 2015. The American Astronomical Society. All rights reserved. The Lyα forest transmission probability distribution function (PDF) is an established probe of the intergalactic medium (IGM) astrophysics, especially the temperature-density relationshi... Read More about IGM constraints from the SDSS-III/BOSS DR9 Lyα forest transmission probability distribution function.

Evidence of patchy hydrogen reionization from an extreme Lyα trough below redshift six (2015)
Journal Article
Becker, G. D., Bolton, J. S., Madau, P., Pettini, M., Ryan-Weber, E. V., & Venemans, B. P. (2015). Evidence of patchy hydrogen reionization from an extreme Lyα trough below redshift six. Monthly Notices of the Royal Astronomical Society, 447(4), 3402-3419. https://doi.org/10.1093/mnras/stu2646

© 2015 The Authors. We report the discovery of an extremely long (~110 Mpc h -1 ) and dark (τ eff ≳ 7) Lyα trough extending down to z ≃ 5.5 towards the z em ≃ 6.0 quasar ULAS J0148+0600. We use these new data in combination with Lya forest measureme... Read More about Evidence of patchy hydrogen reionization from an extreme Lyα trough below redshift six.

The impact of temperature fluctuations on the large-scale clustering of the Lyα forest (2015)
Journal Article
Greig, B., Bolton, J. S., & Wyithe, J. S. B. (2015). The impact of temperature fluctuations on the large-scale clustering of the Lyα forest. Monthly Notices of the Royal Astronomical Society, 447(3), 2503-2511. https://doi.org/10.1093/mnras/stu2624

We develop a semi-analytic method for assessing the impact of the large-scale IGM temperature fluctuations expected following He ii reionization on three-dimensional clustering measurements of the Lyα forest. Our methodology builds upon the existing... Read More about The impact of temperature fluctuations on the large-scale clustering of the Lyα forest.

Gas around galaxy haloes: Methodology comparisons using hydrodynamical simulations of the intergalactic medium (2014)
Journal Article
Meiksin, A., Bolton, J. S., & Tittley, E. R. (2014). Gas around galaxy haloes: Methodology comparisons using hydrodynamical simulations of the intergalactic medium. Monthly Notices of the Royal Astronomical Society, 445(3), 2462-2475. https://doi.org/10.1093/mnras/stu1938

© 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. We perform cosmological simulations of the intergalactic medium (IGM) at redshift z ~ 3 using the numerical gravity-hydrodynamics codes GADGET-3 and... Read More about Gas around galaxy haloes: Methodology comparisons using hydrodynamical simulations of the intergalactic medium.

Heating and ionization of the primordial intergalactic medium by high mass x-ray binaries (2014)
Journal Article
Knevitt, G., Wynn, G., Power, C., & Bolton, J. S. (2014). Heating and ionization of the primordial intergalactic medium by high mass x-ray binaries. Monthly Notices of the Royal Astronomical Society, 445(2), https://doi.org/10.1093/mnras/stu1803

We investigate the influence of high-mass X-ray binaries (HMXBs) on their high-redshift environments. Using a one-dimensional radiative transfer code, we predict the ionization and temperature profiles surrounding a coeval stellar population, compose... Read More about Heating and ionization of the primordial intergalactic medium by high mass x-ray binaries.

Suite of hydrodynamical simulations for the Lyman-alpha forest with massive neutrinos (2014)
Journal Article
Rossi, G., Palanque-Delabrouille, N., Borde, A., Viel, M., Yeche, C., Bolton, J. S., Rich, J., & Le Goff, J.-M. (2014). Suite of hydrodynamical simulations for the Lyman-alpha forest with massive neutrinos. Astronomy and Astrophysics, 567, Article A79. https://doi.org/10.1051/0004-6361/201423507

The signature left in quasar spectra by neutral hydrogen in the Universe allows constraining the sum of the neutrino masses with a better sensitivity than laboratory experiments and may shed new light on the neutrino mass hierarchy and the absolute m... Read More about Suite of hydrodynamical simulations for the Lyman-alpha forest with massive neutrinos.

New approach for precise computation of Lyman-alpha forest power spectrum with hydrodynamical simulations (2014)
Journal Article
Borde, A., Palanque-Delabrouille, N., Rossi, G., Viel, M., Bolton, J. S., Yeche, C., Rich, J., & Le Goff, J.-M. (2014). New approach for precise computation of Lyman-alpha forest power spectrum with hydrodynamical simulations. Journal of Cosmology and Astroparticle Physics, 2014(July), Article 005. https://doi.org/10.1088/1475-7516/2014/07/005

Current experiments are providing measurements of the flux power spectrum from the Lyman-α forests observed in quasar spectra with unprecedented accuracy. Their interpretation in terms of cosmological constraints requires specific simulations of at l... Read More about New approach for precise computation of Lyman-alpha forest power spectrum with hydrodynamical simulations.

The thermal history of the intergalactic medium down to redshift z=1.5: a new curvature measurement (2014)
Journal Article
Boera, E., Murphy, M. T., Becker, G. D., & Bolton, J. S. (2014). The thermal history of the intergalactic medium down to redshift z=1.5: a new curvature measurement. Monthly Notices of the Royal Astronomical Society, 441(3), https://doi.org/10.1093/mnras/stu660

According to the photoheating model of the intergalactic medium (IGM), He ii reionization is expected to affect its thermal evolution. Evidence for additional energy injection into the IGM has been found at 3 ≲ z ≲ 4, though the evidence for the subs... Read More about The thermal history of the intergalactic medium down to redshift z=1.5: a new curvature measurement.

A consistent determination of the temperature of the intergalactic medium at redshift z=2.4 (2014)
Journal Article
Bolton, J. S., Becker, G. D., Haehnelt, M. G., & Viel, M. (2014). A consistent determination of the temperature of the intergalactic medium at redshift z=2.4. Monthly Notices of the Royal Astronomical Society, 438, https://doi.org/10.1093/mnras/stt2374

We present new measurements of the thermal state of the intergalactic medium (IGM) at z∼2.4 derived from absorption line profiles in the Lyα forest. We use a large set of high-resolution hydrodynamical simulations to calibrate the relationship betwee... Read More about A consistent determination of the temperature of the intergalactic medium at redshift z=2.4.

Probing the metallicity and ionization state of the circumgalactic medium at z~6 and beyond with OI absorption (2013)
Journal Article
Keating, L. C., Haehnelt, M. G., Becker, G. D., & Bolton, J. S. (2013). Probing the metallicity and ionization state of the circumgalactic medium at z~6 and beyond with OI absorption. Monthly Notices of the Royal Astronomical Society, 438(2), https://doi.org/10.1093/mnras/stt2324

Low-ionization metal absorption due to O I has been identified as an important probe of the physical state of the intergalactic/circumgalactic medium at the tail end of reionization. We use here high-resolution hydrodynamic simulations to interpret t... Read More about Probing the metallicity and ionization state of the circumgalactic medium at z~6 and beyond with OI absorption.

The one-dimensional Lyα forest power spectrum from BOSS (2013)
Journal Article
Palanque-Delabrouille, N., Yèche, C., Borde, A., Le Goff, J.-M., Rossi, G., Viel, M., Aubourg, É., Bailey, S., Bautista, J., Blomqvist, M., Bolton, A., Bolton, J. S., Busca, N. G., Carithers, B., A. C. Croft, R., Dawson, K. S., Delubac, T., Font-Ribera, A., Ho, S., Kirkby, D., …Weinberg, D. H. (2013). The one-dimensional Lyα forest power spectrum from BOSS. Astronomy and Astrophysics, 559, Article A85. https://doi.org/10.1051/0004-6361/201322130

We have developed two independent methods for measuring the one-dimensional power spectrum of the transmitted flux in the Lyman-α forest. The first method is based on a Fourier transform and the second on a maximum-likelihood estimator. The two metho... Read More about The one-dimensional Lyα forest power spectrum from BOSS.

New measurements of the ionizing ultraviolet background over 2 < z < 5 and implications for hydrogen reionization (2013)
Journal Article
Becker, G. D., & Bolton, J. S. (2013). New measurements of the ionizing ultraviolet background over 2 < z < 5 and implications for hydrogen reionization. Monthly Notices of the Royal Astronomical Society, 436(2), 1023-1039. https://doi.org/10.1093/mnras/stt1610

We present new measurements of the intensity of the ionizing ultraviolet background and the global emissivity of ionizing photons over 2 < z < 5. Our results are based on a suite of updated measurements of physical properties of the high-redshift int... Read More about New measurements of the ionizing ultraviolet background over 2 < z < 5 and implications for hydrogen reionization.

On the rapid demise of Lyman-alpha emitters at z>7 due to the increasing incidence of optically thick absorption systems (2013)
Journal Article
S. Bolton, J., & G. Haehnelt, M. (2013). On the rapid demise of Lyman-alpha emitters at z>7 due to the increasing incidence of optically thick absorption systems. Monthly Notices of the Royal Astronomical Society, 429(2), 1695–1704. https://doi.org/10.1093/mnras/sts455

A variety of independent observational studies have now reported a significant decline in the fraction of Lyman-break galaxies which exhibit Ly-a emission over the redshift interval z=6-7. In combination with the strong damping wing extending redward... Read More about On the rapid demise of Lyman-alpha emitters at z>7 due to the increasing incidence of optically thick absorption systems.

Prospects for detecting the 21 cm forest from the diffuse intergalactic medium with LOFAR (2012)
Journal Article
Ciardi, B., Labropoulos, P., Maselli, A., Thomas, R., Zaroubi, S., Graziani, L., Bolton, J. S., Bernardi, G., Brentjens, M., de Bruyn, A. G., Daiboo, S., Harker, G. J. A., Jelic, V., Kazemi, S., Koopmans, L. V. E., Martinez, O., Mellema, G., Offringa, A. R., Pandey, V. N., Schaye, J., …Yatawatta, S. (2013). Prospects for detecting the 21 cm forest from the diffuse intergalactic medium with LOFAR. Monthly Notices of the Royal Astronomical Society, 428(2), 1755-1765. https://doi.org/10.1093/mnras/sts156

We discuss the feasibility of the detection of the 21 cm forest in the diffuse intergalactic medium (IGM) with the radio telescope LOFAR. The optical depth to the 21 cm line has been derived using simulations of reionization which include detailed ra... Read More about Prospects for detecting the 21 cm forest from the diffuse intergalactic medium with LOFAR.

The intergalactic medium thermal history at redshift z = 1.7–3.2 from the Lyα forest: a comparison of measurements using wavelets and the flux distribution (2012)
Journal Article
Garzilli, A., Bolton, J., -S. Kim, T., Leach, S., & Viel, M. (2012). The intergalactic medium thermal history at redshift z = 1.7–3.2 from the Lyα forest: a comparison of measurements using wavelets and the flux distribution. Monthly Notices of the Royal Astronomical Society, 424(3), 1723-1736. https://doi.org/10.1111/j.1365-2966.2012.21223.x

We investigate the thermal history of the intergalactic medium (IGM) in the redshift interval z = 1.7–3.2 by studying the small-scale fluctuations in the Lyman α forest transmitted flux. We apply a wavelet filtering technique to 18 high-resolution qu... Read More about The intergalactic medium thermal history at redshift z = 1.7–3.2 from the Lyα forest: a comparison of measurements using wavelets and the flux distribution.