Zobrazeno 1 - 10
of 44
pro vyhledávání: '"Witten, Callum"'
Autor:
Witten, Callum, McClymont, William, Laporte, Nicolas, Roberts-Borsani, Guido, Sijacki, Debora, Tacchella, Sandro, Simmonds, Charlotte, Katz, Harley, Ellis, Richard S., Witstok, Joris, Maiolino, Roberto, Ji, Xihan, Hayes, Billy R., Looser, Tobias J., D'Eugenio, Francesco
While JWST has observed galaxies assembling as early as $z\sim14$, evidence of galaxies with significant old stellar populations in the Epoch of Reionisation (EoR) -- the descendants of these earliest galaxies -- are few and far between. Bursty star-
Externí odkaz:
http://arxiv.org/abs/2407.07937
Autor:
McClymont, William, Tacchella, Sandro, D'Eugenio, Francesco, Witten, Callum, Ji, Xihan, Smith, Aaron, Maiolino, Roberto, Scholtz, Jan, Simmonds, Charlotte, Witstok, Joris
The peculiar nebular emission displayed by galaxies in the early Universe presents a unique opportunity to gain insight into the regulation of star formation in extreme environments. We investigate 500 (109) galaxies with deep NIRSpec/PRISM observati
Externí odkaz:
http://arxiv.org/abs/2405.15859
Autor:
Cameron, Alex J., Katz, Harley, Witten, Callum, Saxena, Aayush, Laporte, Nicolas, Bunker, Andrew J.
We identify a low-metallicity ($12+\log({\rm O}/{\rm H})=7.59$) Ly$\alpha$-emitting galaxy at $z=5.943$ with evidence of a strong Balmer jump, arising from nebular continuum. While Balmer jumps are sometimes observed in low-redshift star-forming gala
Externí odkaz:
http://arxiv.org/abs/2311.02051
Autor:
Scholtz, Jan, Witten, Callum, Laporte, Nicolas, Ubler, Hannah, Perna, Michele, Maiolino, Roberto, Arribas, Santiago, Baker, William, Bennett, Jake, D'Eugenio, Francesco, Tacchella, Sandro, Witstok, Joris, Bunker, Andrew, Carniani, Stefano, Charlot, Stephane, Cresci, Giovanni, Curtis-Lake, Emma, Eisenstein, Daniel, Kumari, Nimisha, Robertson, Brant, Del Pino, Bruno Rodriguez, Simmonds, Charlotte, Smit, Renske, Venturi, Giacomo, Williams, Christina, Willmer, Christopher
Publikováno v:
A&A 687, A283 (2024)
Recent observations with the \textit{James Webb} Space Telescope (JWST) have further refined the spectroscopic redshift of GN-z11, one of the most distant galaxies identified with the \textit{Hubble} Space Telescope (HST) at $z=10.603$. The presence
Externí odkaz:
http://arxiv.org/abs/2306.09142
Autor:
Maiolino, Roberto, Uebler, Hannah, Perna, Michele, Scholtz, Jan, D'Eugenio, Francesco, Witten, Callum, Laporte, Nicolas, Witstok, Joris, Carniani, Stefano, Tacchella, Sandro, Baker, William, Arribas, Santiago, Nakajima, Kimihiko, Eisenstein, Daniel, Bunker, Andrew, Charlot, Stephane, Cresci, Giovanni, Curti, Mirko, Curtis-Lake, Emma, de Graaff, Anna, Ji, Zhiyuan, Johnson, Benjamin D., Kumari, Nimisha, Looser, Tobias J., Maseda, Michael, Nelson, Erica, Robertson, Brant, Del Pino, Bruno Rodriguez, Sandles, Lester, Simmonds, Charlotte, Smit, Renske, Sun, Fengwu, Venturi, Giacomo, Williams, Christina, Willmer, Christopher
Publikováno v:
A&A 687, A67 (2024)
Finding the first generation of stars formed out of pristine gas in the early Universe, known as Population III (PopIII) stars, is one of the most important goals of modern astrophysics. Recent models have suggested that PopIII stars may form in pock
Externí odkaz:
http://arxiv.org/abs/2306.00953
High-redshift quasars ($z\gtrsim6$), powered by black holes (BHs) with large inferred masses, imply rapid BH growth in the early Universe. The most extreme examples have inferred masses of $\sim \! 10^9\,$M$_\odot$ at $z = 7.5$ and $\sim \! 10^{10}\,
Externí odkaz:
http://arxiv.org/abs/2305.11932
Autor:
Witten, Callum, Laporte, Nicolas, Martin-Alvarez, Sergio, Sijacki, Debora, Yuan, Yuxuan, Haehnelt, Martin G., Baker, William M., Dunlop, James S., Ellis, Richard S., Grogin, Norman A., Illingworth, Garth, Katz, Harley, Koekemoer, Anton M., Magee, Daniel, Maiolino, Roberto, McClymont, William, Pérez-González, Pablo G., Puskás, David, Roberts-Borsani, Guido, Santini, Paola, Simmonds, Charlotte
During the epoch of reionisation the first galaxies were enshrouded in pristine neutral gas, with one of the brightest emission lines in star-forming galaxies, Lyman-$\alpha$ (Ly$\alpha$), expected to remain undetected until the Universe became ionis
Externí odkaz:
http://arxiv.org/abs/2303.16225
Autor:
Simmonds, Charlotte, Tacchella, Sandro, Maseda, Michael V., Williams, Christina, Baker, William M., Witten, Callum, Johnson, Benjamin D., Robertson, Brant, Saxena, Aayush, Sun, Fengwu, Witstok, Joris, Bhatawdekar, Rachana, Boyett, Kristan, Bunker, Andrew J., Charlot, Stephane, Curtis-Lake, Emma, Egami, Eiichi, Eisenstein, Daniel J., Ji, Zhiyuan, Maiolino, Roberto, Sandles, Lester, Smit, Renske, Übler, Hannah, Willott, Chris
We study the ionising photon production efficiency at the end of the Epoch of Reionisation ($z \sim 5.4 - 6.6$) for a sample of 30 Lyman-$\alpha$ emitters. This is a crucial quantity to infer the ionising photon budget of the Universe. These objects
Externí odkaz:
http://arxiv.org/abs/2303.07931
Although low-mass star-forming galaxies are the leading candidates of the reionisation process, we cannot conclusively rule out high-mass star-forming galaxies as candidates. While most simulations indicate the former is the best candidate some model
Externí odkaz:
http://arxiv.org/abs/2301.03599
Autor:
Witten, Callum E. C., Aguado, David S., Sanders, Jason L., Belokurov, Vasily, Evans, N. Wyn, Koposov, Sergey E., Prieto, Carlos Allende, De Angeli, Francesca, Irwin, Mike J.
Gaia Data Release 3 has provided the astronomical community with the largest stellar spectroscopic survey to date ($>$ 220 million sources). The low resolution (R$\sim$50) blue photometer (BP) and red photometer (RP) spectra will allow for the estima
Externí odkaz:
http://arxiv.org/abs/2205.12271