Browsing by Title

Host Dark Matter Halos of SDSS Red and Blue Quasars: No Significant Difference in Large-scale Environment

Petter, Grayson C.; Hickox, Ryan C.; Alexander, David M.; Geach, James E.; Myers, Adam D.; Rosario, David J.; Fawcett, Victoria A.; Klindt, Lizelke; Whalen, Kelly E. (2022-03-02)

The observed optical colors of quasars are generally interpreted in one of two frameworks: unified models that attribute the color to the random orientation of the accretion disk along the line of sight, and evolutionary ...

Host Dark Matter Halos of Wide-field Infrared Survey Explorer-selected Obscured and Unobscured Quasars: Evidence for Evolution

Petter, Grayson C.; Hickox, Ryan C.; Alexander, David M.; Myers, Adam D.; Geach, James E.; Whalen, Kelly E.; Andonie, Carolina P. (2023-03-23)

Obscuration in quasars may arise from steep viewing angles along the dusty torus, or instead may represent a distinct phase of supermassive black hole growth. We test these scenarios by probing the host dark matter halo ...

The host galaxies of flat-spectrum quasars

Jarvis, M.J.; McLure, R.J. (2003)

The Host Galaxies of Hybrid Morphology Radio Sources

Stroe, Andra; Catlett, Victoria; Harwood, Jeremy J.; Vernstrom, Tessa; Mingo, Beatriz (2022-12-16)

Based on their differing radio morphologies, powerful radio galaxies can be separated into the Fanaroff-Riley I (FR I) and II (FR II) classes. Hybrid morphology radio sources (HyMoRS) contain morphologies consistent with ...

Host pathogen interactions in relation to management of light leaf spot disease (caused by Pyrenopeziza brassicae) on Brassica species

Karandeni Dewage, Chinthani Shanika; Klöppel, Coretta A.; Stotz, Henrik U.; Fitt, Bruce D. L. (2017)

Light leaf spot, caused by Pyrenopeziza brassicae, is currently the most damaging disease problem in oilseed rape in the UK. According to recent survey data, the severity of epidemics has increased progressively across the ...

Host plant root exudates reduce phytonematode cuticle aging to maintain Pasteuria endospore attachment

Mohan, Sharad; Kumar, Kiran; Davies, Keith (2022-03-17)

Endospores of the nematode hyperparasite from the Pasteuria group of Gram-positive bacteria have the potential to suppress phytonematode populations and reduce root infection. Parasitism by the bacteria commences when ...

Host species determines egg size in Oriental cuckoo

Meshcheryagina, S. G.; Mashanova, A.; Bachurin, G. N.; Mitiay, I. S.; Golovatin, M. G. (2018-11-02)

The Oriental cuckoo Cuculus optatus is an obligate brood parasite associated with species of the genus Phylloscopus. Four distinct phenotypes of Oriental cuckoo eggs, matching eggshell colour patterns of Arctic warbler ...

Host specificity exhibited by populations of endospores of Pasteuria penetrans to the juvenile and male cuticles of Meloidogyne hapla

Davies, Keith G.; Williamson, Valerie M. (2006)

The host stars of extrasolar planets have normal lithium abundances

Ryan, Sean G. (2000)

The lithium abundances of planet-harbouring stars have been compared with those of open clusters and field stars. Young (chromospherically active) and subgiant stars have been eliminated from the comparison because they ...

Hostile Environments: Immigration and Food Poverty in the UK

Hamilton, Laura; Thompson, Claire; Wills, Wendy (University of Hertfordshire, 2022-12-13)

As part of The Food Foundation’s wider project to re-shape the public narrative on food and inequalities, this research was commissioned to focus on families with NRPF and food poverty. The aim of this study was to explore ...

Hot and cold gas accretion and feedback in radio-loud active galaxies

Hardcastle, M.J.; Evans, D.A.; Croston, J.H. (2007)

We have recently shown that X-ray observations of the population of ‘low-excitation’ radio galaxies, which includesmost low-power, Fanaroff-Riley class I sources as well as some more powerful Fanaroff-Riley class II objects, ...

The hot gas distribution, X-ray luminosity and baryon budget in the L-Galaxies semi-analytic model of galaxy formation

Zhong, Wenxin; Fu, Jian; Sharma, Prateek; Shen, Shiyin; Yates, Robert M. (2023-03-31)

Hot ionized gas is important in the baryon cycle of galaxies and contributes the majority of their ``missing baryons''. Until now, most semi-analytic models of galaxy formation have paid little attention to hot gaseous ...

Hot subdwarf stars in close-up view. I. Rotational properties of subdwarf B stars in close binary systems and nature of their unseen companions

Geier, S.; Heber, U.; Podsiadlowski, P.; Edelmann, H.; Napiwotzki, R.; Kupfer, T.; Muller, S. (2010)

The origin of hot subdwarf B stars (sdBs) is still unclear. About half of the known sdBs are in close binary systems for which common envelope ejection is the most likely formation channel. Little is known about this dynamic ...

Hot subdwarfs from the ESO Supernova Ia Progenitor Survey. I. Atmospheric parameters and cool companions of sdB stars

Lisker, T.; Heber, U.; Napiwotzki, R.; Christlieb, N.; Han, Z.; Homeier, D.; Reimers, D. (2005-01)

A hot Uranus orbiting the super metal-rich star 77338 and the metallicity-mass connection

Jenkins, J. S.; Jones, H.R.A.; Tuomi, M.; Murgas, F.; Hoyer, S.; Jones, M. I.; Barnes, J. R.; Pavlenko, Y. V.; Ivanyuk, O.; Rojo, P.; Jordan, A.; Day-Jones, A. C.; Ruiz, M. T.; Pinfield, D.J. (2013-04-01)

We announce the discovery of a low-mass planet orbiting the super metal-rich K0V star HD 77338 as part of our ongoing Calan-Hertfordshire Extrasolar Planet Search. The best-fit planet solution has an orbital period of ...

Hot UV bright stars in globular clusters

Moehler, S.; Landsmann, W.; Napiwotzki, R. (1998)

We have obtained medium-resolution spectra of seven UV-bright stars discovered on images of four southern globular clusters obtained with the Ultraviolet Imaging Telescope (UIT). Effective temperatures, surface gravities ...

The hot-Jupiter Kepler-17b : Discovery, obliquity from stroboscopic starspots, and atmospheric characterization

Désert, J.-M.; Charbonneau, D.; Ballard, S.; Carter, J.A.; Quinn, S.N.; Fressin, F.; Latham, D.W.; Torres, G.; Lissauer, J.J.; Sasselov, D.D.; Demory, B.-O.; Seager, S.; Winn, J.N.; Fortney, J.J.; Fabrycky, D.C.; Cochran, W.D.; Endl, M.; MacQueen, P.J.; Isaacson, H.T.; Knutson, H.A.; Marcy, G.W.; Buchhave, L.A.; Bryson, S.T.; Rowe, J.F.; Borucki, W.J.; Christiansen, J.L.; Haas, M.R.; Koch, D.; Batalha, N.M.; Brown, T.M.; Caldwell, D.A.; Jenkins, J.M.; Mullally, F.; Tenenbaum, P.; Deming, D.; Ford, E.B.; Gilliland, R.L.; Gillon, M.; Kinemuchi, K.; Still, M.; Lucas, P.W.; Uddin, K. (2011-11-01)

This paper reports the discovery and characterization of the transiting hot giant exoplanet Kepler-17b. The planet has an orbital period of 1.486 days, and radial velocity measurements from the Hobby-Eberly Telescope show ...

University of Hertfordshire Research Archive