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10 results on '"Wilkins, SM"'

1. Probing similar to L-* Lyman-break galaxies at z approximate to 7 in GOODS-South with WFC3 on Hubble Space Telescope

Author

Wilkins, SM, Bunker, AJ, Ellis, RS, Stark, D, Stanway, ER, Chiu, K, Lorenzoni, S, and Jarvis, MJ

Abstract

We analyse recently acquired near-infrared Hubble Space Telescope imaging of the Great Observatories Origins Deep Survey (GOODS)-South field to search for star-forming galaxies at z≈ 7.0. By comparing Wide Field Camera 3 (WFC3) 0.98 μm Y-band images with Advanced Camera for Surveys (ACS)z-band (0.85 μm) images, we identify objects with colours consistent with Lyman-break galaxies at z≃ 6.4-7.4. This new data cover an area five times larger than that previously reported in the WFC3 imaging of the Hubble Ultra Deep Field and affords a valuable constraint on the bright end of the luminosity function. Using additional imaging of the region in the ACS B,V and i bands from GOODS v2.0 and the WFC. 3J band, we attempt to remove any low-redshift interlopers. Our selection criteria yields six candidates brighter than YAB= 27.0, of which all except one are detected in the ACS z-band imaging and are thus unlikely to be transients. Assuming all six candidates are atz≈ 7, this implies a surface density of objects brighter than YAB= 27.0 of 0.30 ± 0.12 arcmin-2, a value significantly smaller than the prediction from z≈ 6 luminosity function. This suggests continued evolution of the bright end of the luminosity function betweenz= 6 and 7, with number densities lower at higher redshift. © 2010 The Authors. Journal compilation © 2010 RAS.

Published
2016

2. Spectroscopy of z similar to 7 candidate galaxies: using Lyman alpha to constrain the neutral fraction of hydrogen in the high-redshift universe

Author

Caruana, J, Bunker, AJ, Wilkins, SM, Stanway, ER, Lorenzoni, S, Jarvis, MJ, and Ebert, H

Abstract

Following our previous spectroscopic observations of z > 7 galaxies with Gemini/Gemini Near Infra-Red Spectrograph (GNIRS) and Very Large Telescope (VLT)/XSHOOTER, which targeted a total of eight objects,we present here our results froma deeper and largerVLT/FOcal Reducer and Spectrograph (FORS2) spectroscopic sample of Wide Field Camera 3 selected z>7 candidate galaxies.With our FORS2 setup we cover the 737-1070 nm wavelength range, enabling a search for Lyman α in the redshift range spanning 5.06-7.80. We target 22 z-band dropouts and nd no evidence of Lyman α emission, with the exception of a tentative detection (

Published
2016
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3. The ultraviolet properties of star-forming galaxies - I. HST WFC3 observations of very high redshift galaxies

Author

Wilkins, SM, Bunker, AJ, Stanway, E, Lorenzoni, S, and Caruana, J

Subjects
Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics::Galaxy Astrophysics, QB
Abstract

The acquisition of deep near-IR imaging with Wide Field Camera 3 on the Hubble Space Telescope has provided the opportunity to study the very high redshift Universe. For galaxies up to z≈ 7.7 sufficient wavelength coverage exists to probe the rest-frame ultraviolet (UV) continuum without contamination from either Lyman α emission or the Lyman α break. In this work we use near-infrared (near-IR) imaging to measure the rest-frame UV continuum colours of galaxies at 4.7 < z < 7.7. We have carefully defined a colour-colour selection to minimize any inherent bias in the measured UV continuum slope for the drop-out samples. For the highest redshift sample (6.7 < z < 7.7), selected as zf850lp-band drop-outs, we find mean UV continuum colours approximately equal to zero (AB), consistent with a dust-free, solar metallicity, star-forming population (or a moderately dusty population of low metallicity). At lower redshift we find that the mean UV continuum colours of galaxies (over the same luminosity range) are redder, and that galaxies with higher luminosities are also slightly redder on average. One interpretation of this is that lower redshift and more luminous galaxies are dustier; however, this interpretation is complicated by the effects of the star formation history and metallicity and potentially the initial mass function on the UV continuum colours. © 2011 The Authors Monthly Notices of the Royal Astronomical Society © 2011 RAS.

Published
2011

5. A 'Psychology Core Graphics Resource Pack' for HE: the development of a resource to support blind and visually impaired students in higher education.

Author

Gray G and Wilkins SM

Abstract

This project investigated the provision of a set of core tactile and large print diagrams and supporting materials for degree level psychology study, containing diagrams that are central to the majority of UK psychology courses, as an alternative to providing many different bespoke diagrams for individual students. Interviews with 12 blind and visually impaired psychology students and graduates and four psychology lecturers established that such a pack would be a useful resource. After in-depth research of the psychology curriculum and reviews of popular textbooks, a prototype 'Psychology Core Graphics Resource Pack' was designed in further consultation with end-users and experts. This contained 33 core tactile and large print diagrams, descriptions of 21 other images, and good practice guidelines for staff and students with a range of visual impairments and tactile diagram experience. An initial evaluation with three visually impaired participants confirmed that the pack was a beneficial resource for blind and visually impaired psychology students and staff at a range of levels. The final challenge for the project is to establish how best to market, produce and disseminate packs to relevant end-users on a larger scale. Copyright © 2005 SAGE Publications Ltd. [ABSTRACT FROM AUTHOR]

Published
2005
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6. CEERS Key Paper V: A triality on the nature of HST-dark galaxies

Author

Pablo G. Pérez-González, Guillermo Barro, Marianna Annunziatella, Luca Costantin, Ángela García-Argumánez, Elizabeth J. McGrath, Rosa M. Mérida, Jorge A. Zavala, Pablo Arrabal Haro, Micaela B. Bagley, Bren E. Backhaus, Peter Behroozi, Eric F. Bell, Laura Bisigello, Véronique Buat, Antonello Calabrò, Caitlin M. Casey, Nikko J. Cleri, Rosemary T. Coogan, M. C. Cooper, Asantha R. Cooray, Avishai Dekel, Mark Dickinson, David Elbaz, Henry C. Ferguson, Steven L. Finkelstein, Adriano Fontana, Maximilien Franco, Jonathan P. Gardner, Mauro Giavalisco, Carlos Gómez-Guijarro, Andrea Grazian, Norman A. Grogin, Yuchen Guo, Marc Huertas-Company, Shardha Jogee, Jeyhan S. Kartaltepe, Lisa J. Kewley, Allison Kirkpatrick, Dale D. Kocevski, Anton M. Koekemoer, Arianna S. Long, Jennifer M. Lotz, Ray A. Lucas, Casey Papovich, Nor Pirzkal, Swara Ravindranath, Rachel S. Somerville, Sandro Tacchella, Jonathan R. Trump, Weichen Wang, Stephen M. Wilkins, Stijn Wuyts, Guang Yang, L. Y. Aaron Yung, Pérez-González, PG [0000-0003-4528-5639], Barro, G [0000-0001-6813-875X], Annunziatella, M [0000-0002-8053-8040], Costantin, L [0000-0001-6820-0015], García-Argumánez, Á [0000-0002-8365-5525], McGrath, EJ [0000-0001-8688-2443], Mérida, RM [0000-0001-8115-5845], Zavala, JA [0000-0002-7051-1100], Haro, PA [0000-0002-7959-8783], Bagley, MB [0000-0002-9921-9218], Backhaus, BE [0000-0001-8534-7502], Behroozi, P [0000-0002-2517-6446], Bell, EF [0000-0002-5564-9873], Bisigello, L [0000-0003-0492-4924], Buat, V [0000-0003-3441-903X], Calabrò, A [0000-0003-2536-1614], Casey, CM [0000-0002-0930-6466], Cleri, NJ [0000-0001-7151-009X], Coogan, RT [0000-0002-4343-0479], Cooper, MC [0000-0003-1371-6019], Cooray, AR [0000-0002-3892-0190], Dekel, A [0000-0003-4174-0374], Dickinson, M [0000-0001-5414-5131], Elbaz, D [0000-0002-7631-647X], Ferguson, HC [0000-0001-7113-2738], Finkelstein, SL [0000-0001-8519-1130], Fontana, A [0000-0003-3820-2823], Franco, M [0000-0002-3560-8599], Gardner, JP [0000-0003-2098-9568], Giavalisco, M [0000-0002-7831-8751], Gómez-Guijarro, C [0000-0002-4085-9165], Grazian, A [0000-0002-5688-0663], Grogin, NA [0000-0001-9440-8872], Guo, Y [0000-0002-4162-6523], Huertas-Company, M [0000-0002-1416-8483], Jogee, S [0000-0002-1590-0568], Kartaltepe, JS [0000-0001-9187-3605], Kewley, LJ [0000-0001-8152-3943], Kirkpatrick, A [0000-0002-1306-1545], Kocevski, DD [0000-0002-8360-3880], Koekemoer, AM [0000-0002-6610-2048], Long, AS [0000-0002-7530-8857], Lotz, JM [0000-0003-3130-5643], Lucas, RA [0000-0003-1581-7825], Papovich, C [0000-0001-7503-8482], Pirzkal, N [0000-0003-3382-5941], Ravindranath, S [0000-0002-5269-6527], Somerville, RS [0000-0002-6748-6821], Tacchella, S [0000-0002-8224-4505], Trump, JR [0000-0002-1410-0470], Wang, W [0000-0002-9593-8274], Wilkins, SM [0000-0003-3903-6935], Wuyts, S [0000-0003-3735-1931], Yang, G [0000-0001-8835-7722], Aaron Yung, LY [0000-0003-3466-035X], and Apollo - University of Cambridge Repository

Subjects
Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), FOS: Physical sciences, Astronomy and Astrophysics, 5109 Space Sciences, 51 Physical Sciences, Astrophysics - Astrophysics of Galaxies
Abstract

The new capabilities that JWST offers in the near- and mid-infrared (IR) are used to investigate in unprecedented detail the nature of optical/near-IR faint, mid-IR bright sources, HST-dark galaxies among them. We gather JWST data from the CEERS survey in the EGS, jointly with HST data, and analyze spatially resolved optical-to-mid-IR spectral energy distributions (SEDs) to estimate both photometric redshifts in 2 dimensions and stellar populations properties in a pixel-by-pixel basis. We select 138 galaxies with F150W-F356W>1.5 mag, F356W100 Gyr^-1); (2) 18% are quiescent/dormant (i.e., subject to reignition and rejuvenation) galaxies at 3, Comment: Published in CEERS ApJL Focus Issue, ApJL 946, L16

Published
2022
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7. On the Stellar Populations of Galaxies at z=9-11: The Growth of Metals and Stellar Mass at Early Times

Author

Sandro Tacchella, Steven L. Finkelstein, Micaela Bagley, Mark Dickinson, Henry C. Ferguson, Mauro Giavalisco, Luca Graziani, Norman A. Grogin, Nimish Hathi, Taylor A. Hutchison, Intae Jung, Anton M. Koekemoer, Rebecca L. Larson, Casey Papovich, Norbert Pirzkal, Sofía Rojas-Ruiz, Mimi Song, Raffaella Schneider, Rachel S. Somerville, Stephen M. Wilkins, L. Y. Aaron Yung, Tacchella, S [0000-0002-8224-4505], Finkelstein, SL [0000-0001-8519-1130], Bagley, M [0000-0002-9921-9218], Dickinson, M [0000-0001-5414-5131], Ferguson, HC [0000-0001-7113-2738], Giavalisco, M [0000-0002-7831-8751], Graziani, L [0000-0002-9231-1505], Grogin, NA [0000-0001-9440-8872], Hathi, N [0000-0001-6145-5090], Hutchison, TA [0000-0001-6251-4988], Jung, I [0000-0003-1187-4240], Koekemoer, AM [0000-0002-6610-2048], Larson, RL [0000-0003-2366-8858], Papovich, C [0000-0001-7503-8482], Rojas-Ruiz, S [0000-0003-2349-9310], Song, M [0000-0002-8442-3128], Wilkins, SM [0000-0003-3903-6935], Yung, LYA [0000-0003-3466-035X], and Apollo - University of Cambridge Repository

Subjects
Early universe, Galaxy formation, Galaxy evolution, High-redshift galaxies, Star formation, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics - Astrophysics of Galaxies, Space and Planetary Science, 5101 Astronomical Sciences, Astrophysics of Galaxies (astro-ph.GA), Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, 51 Physical Sciences, Astrophysics::Galaxy Astrophysics
Abstract

We present a detailed stellar population analysis of 11 bright ($H10$., Comment: 27 pages + Appendix; accepted by ApJ

Published
2021

8. Confirmation and refutation of very luminous galaxies in the early Universe.

Author

Arrabal Haro P, Dickinson M, Finkelstein SL, Kartaltepe JS, Donnan CT, Burgarella D, Carnall AC, Cullen F, Dunlop JS, Fernández V, Fujimoto S, Jung I, Krips M, Larson RL, Papovich C, Pérez-González PG, Amorín RO, Bagley MB, Buat V, Casey CM, Chworowsky K, Cohen SH, Ferguson HC, Giavalisco M, Huertas-Company M, Hutchison TA, Kocevski DD, Koekemoer AM, Lucas RA, McLeod DJ, McLure RJ, Pirzkal N, Seillé LM, Trump JR, Weiner BJ, Wilkins SM, and Zavala JA

Abstract

During the first 500 million years of cosmic history, the first stars and galaxies formed, seeding the Universe with heavy elements and eventually reionizing the intergalactic medium 1-3 . Observations with the James Webb Space Telescope (JWST) have uncovered a surprisingly high abundance of candidates for early star-forming galaxies, with distances (redshifts, z), estimated from multiband photometry, as large as z ≈ 16, far beyond pre-JWST limits 4-9 . Although such photometric redshifts are generally robust, they can suffer from degeneracies and occasionally catastrophic errors. Spectroscopic measurements are required to validate these sources and to reliably quantify physical properties that can constrain galaxy formation models and cosmology 10 . Here we present JWST spectroscopy that confirms redshifts for two very luminous galaxies with z > 11, and also demonstrates that another candidate with suggested z ≈ 16 instead has z = 4.9, with an unusual combination of nebular line emission and dust reddening that mimics the colours expected for much more distant objects. These results reinforce evidence for the early, rapid formation of remarkably luminous galaxies while also highlighting the necessity of spectroscopic verification. The large abundance of bright, early galaxies may indicate shortcomings in current galaxy formation models or deviations from physical properties (such as the stellar initial mass function) that are generally believed to hold at later times., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Published
2023
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9. Strange Bedfellows? Common Ground on the Moral Status Question.

Author

Wilkins SM

Subjects
Ethical Analysis, Humans, Infant, Newborn, Philosophy, Medical, Stem Cell Research ethics, Abortion, Induced ethics, Infanticide ethics, Morals, Personhood
Abstract

When does a developing human being acquire moral status? I outline three different positions based on substance ontology that attempt to solve the question by locating some morally salient event in the process of human development question. In the second section, I consider some specific empirical objections to one of these positions, refute them, and then show how similar objections and responses would generalize to the other substance-based positions on the question. The crucial finding is that all the attempts to answer the question that involve substance ontology need to appeal to dispositions., (© The Author 2016. Published by Oxford University Press, on behalf of the Journal of Medicine and Philosophy Inc. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Published
2016
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