The Lyman Continuum Escape Fraction of Star-forming Galaxies at 2.4 ≲ <i>z</i> ≲ 3.0 from UVCANDELS
Xin Wang, Harry I. Teplitz, Brent M. Smith, Rogier A. Windhorst, Marc Rafelski, Vihang Mehta, Anahita Alavi, Zhiyuan Ji, Gabriel Brammer, James Colbert, Norman A. Grogin, Nimish P. Hathi, Anton M. Koekemoer, Laura Prichard, Claudia Scarlata, Ben Sunnquist, Pablo Arrabal Haro, Christopher J. Conselice, Eric Gawiser, Yicheng Guo, Matthew Hayes, Rolf A. Jansen, Ray A. Lucas, R. W. O’Connell, Brant Robertson, Michael Rutkowski, Brian Siana, E. Vanzella, Teresa Ashcraft, Micaela B. Bagley, Ivano Baronchelli, Guillermo Barro, Alex Blanche, Adam Broussard, Timothy Carleton, Nima Chartab, Y. Cheng, Alex Codoreanu, Seth H. Cohen, Y. Sophia Dai, Behnam Darvish, Romeel Davé, Laura DeGroot, D. F. de Mello, Mark Dickinson, Najmeh Emami, Henry C. Ferguson, Leonardo Ferreira, Keely Finkelstein, Steven L. Finkelstein, Jonathan P. Gardner, Timothy Gburek, Mauro Giavalisco, Andrea Grazian, Caryl Gronwall, Shoubaneh Hemmati, Justin Howell, Kartheik Iyer, Sugata Kaviraj, Peter Kurczynski, Ilin Lazar, John MacKenty, Kameswara Bharadwaj Mantha, Alec Martin, Garreth Martin, Tyler McCabe, Bahram Mobasher, Kalina Nedkova, Charlotte Olsen, Lillian Otteson, Swara Ravindranath, Caleb Redshaw, Zahra Sattari, Emmaris Soto, L. Y. Aaron Yung, Bonnabelle Zabelle, the UVCANDELS team
Abstract
Abstract The UltraViolet Imaging of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey Fields (UVCANDELS) survey is a Hubble Space Telescope (HST) Cycle-26 Treasury Program, allocated in total 164 orbits of primary Wide-Field Camera 3 Ultraviolet and VISible light F275W imaging with coordinated parallel Advanced Camera for Surveys F435W imaging, on four of the five premier extragalactic survey fields: GOODS-N, GOODS-S, EGS, and COSMOS. We introduce this survey by presenting a comprehensive analysis of the absolute escape fraction ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>f</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">esc</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">abs</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> ) of Lyman continuum radiation through stacking the UV images of a population of star-forming galaxies with secure redshifts at 2.4 ≤ z ≤ 3.0. Our stacking benefits from the catalogs of high-quality spectroscopic redshifts compiled from archival ground-based data and HST slitless spectroscopy, carefully vetted by dedicated visual inspection efforts. We develop a robust stacking method to apply to 10 samples of in total 56 galaxies, and perform detailed Monte Carlo simulations of the intergalactic medium (IGM) attenuation, to take into account the sample variance of the mean IGM transmission when measuring <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>f</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">esc</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">abs</mml:mi> </mml:mrow> </mml:msubsup> </mml:math> . The full stack at z ≈ 2.44 from 28 galaxies places a stringent 1 σ upper limit of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>f</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">esc</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">abs</mml:mi> </mml:mrow> </mml:msubsup> <mml:mo>≲</mml:mo> <mml:mn>5</mml:mn> <mml:mo>%</mml:mo> </mml:math> , whereas the full stack at z ≈ 2.72 of an equal number of galaxies gives an upper limit of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msubsup> <mml:mrow> <mml:mi>f</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">esc</mml:mi> </mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">abs</mml:mi> </mml:mrow> </mml:msubsup> <mml:mo>≲</mml:mo> <mml:mn>26</mml:mn> <mml:mo>%</mml:mo> </mml:math> at 1 σ confidence level. These new F275W and F435W imaging mosaics from UVCANDELS have been made publicly available on the Barbara A. Mikulski Archive for Space Telescopes.