%0 Generic %1 robertsborsani2022faint %A Roberts-Borsani, Guido %A Treu, Tommaso %A Chen, Wenlei %A Morishita, Takahiro %A Vanzella, Eros %A Zitrin, Adi %A Bergamini, Pietro %A Castellano, Marco %A Fontana, Adriano %A Grillo, Claudio %A Kelly, Patrick L. %A Merlin, Emiliano %A Paris, Diego %A Rosati, Piero %A Acebron, Ana %A Bonchi, Andrea %A Boyett, Kit %A Bradac, Marusa %A Broadhurst, Tom %A Calabro, Antonello %A Diego, Jose M. %A Dressler, Alan %A Furtak, Lukas J. %A Filippenko, Alexei V. %A Glazebrook, Karl %A Koekemoer, Anton M. %A Leethochawalit, Nicha %A Malkan, Matthew A. %A Mason, Charlotte %A Mercurio, Amata %A Metha, Benjamin %A Nanayakkara, Themiya %A Pentericci, Laura %A Pierel, Justin %A Rieck, Steven %A Roy, Namrata %A Santini, Paola %A Strait, Victoria %A Strausbaugh, Robert %A Trenti, Michele %A Vulcani, Benedetta %A Wang, Lifan %A Wang, Xin %A Windhorst, Rogier %A Yang, Lilan %D 2022 %K library %T A shot in the Dark (Ages): a faint galaxy at $z=9.76$ confirmed with JWST %U http://arxiv.org/abs/2210.15639 %X The appearance of galaxies over the first billion years after the Big Bang is believed to be responsible for the last dramatic change in the state of the Universe. Ultraviolet photons from galaxies within this time period - the Epoch of Reionization - ionized intergalactic Hydrogen, rendering the Universe transparent to UV radiation and ending the so-called cosmic Dark Ages, sometime after redshift $z\sim8$. The majority of ionizing photons in the first few hundred Myrs of cosmic history are thought to derive from galaxies significantly fainter than the characteristic luminosity $L^*$. These faint galaxies are thought to be surrounded by sufficient neutral gas to prevent the escape of the Lyman-$\alpha$ photons that would allow confirmation with current observatories. Here we demonstrate the power of the recently commissioned James Webb Space Telescope to transform our understanding of the sources of reionization, by reporting the first spectroscopic confirmation of a very low luminosity ($\sim0.05 L^*$) galaxy at $z=9.76$, observed 480 Myr after the Big Bang, via the detection of the Lyman-break and redward continuum with the NIRSpec and NIRCam instruments. The galaxy JD1 is gravitationally magnified by a factor of $\mu\sim13$ by the foreground cluster A2744. The power of JWST and lensing allows us to peer deeper than ever before into the cosmic Dark Ages, revealing the compact ($\sim$150 pc) and complex morphology and physical properties of an ultrafaint galaxy ($M_UV=-17.45$).

@misc{robertsborsani2022faint, abstract = {The appearance of galaxies over the first billion years after the Big Bang is believed to be responsible for the last dramatic change in the state of the Universe. Ultraviolet photons from galaxies within this time period - the Epoch of Reionization - ionized intergalactic Hydrogen, rendering the Universe transparent to UV radiation and ending the so-called cosmic Dark Ages, sometime after redshift $z\sim8$. The majority of ionizing photons in the first few hundred Myrs of cosmic history are thought to derive from galaxies significantly fainter than the characteristic luminosity $L^{*}$. These faint galaxies are thought to be surrounded by sufficient neutral gas to prevent the escape of the Lyman-$\alpha$ photons that would allow confirmation with current observatories. Here we demonstrate the power of the recently commissioned James Webb Space Telescope to transform our understanding of the sources of reionization, by reporting the first spectroscopic confirmation of a very low luminosity ($\sim0.05 L^{*}$) galaxy at $z=9.76$, observed 480 Myr after the Big Bang, via the detection of the Lyman-break and redward continuum with the NIRSpec and NIRCam instruments. The galaxy JD1 is gravitationally magnified by a factor of $\mu\sim13$ by the foreground cluster A2744. The power of JWST and lensing allows us to peer deeper than ever before into the cosmic Dark Ages, revealing the compact ($\sim$150 pc) and complex morphology and physical properties of an ultrafaint galaxy ($M_{\rm UV}=-17.45$).}, added-at = {2022-10-28T14:17:50.000+0200}, author = {Roberts-Borsani, Guido and Treu, Tommaso and Chen, Wenlei and Morishita, Takahiro and Vanzella, Eros and Zitrin, Adi and Bergamini, Pietro and Castellano, Marco and Fontana, Adriano and Grillo, Claudio and Kelly, Patrick L. and Merlin, Emiliano and Paris, Diego and Rosati, Piero and Acebron, Ana and Bonchi, Andrea and Boyett, Kit and Bradac, Marusa and Broadhurst, Tom and Calabro, Antonello and Diego, Jose M. and Dressler, Alan and Furtak, Lukas J. and Filippenko, Alexei V. and Glazebrook, Karl and Koekemoer, Anton M. and Leethochawalit, Nicha and Malkan, Matthew A. and Mason, Charlotte and Mercurio, Amata and Metha, Benjamin and Nanayakkara, Themiya and Pentericci, Laura and Pierel, Justin and Rieck, Steven and Roy, Namrata and Santini, Paola and Strait, Victoria and Strausbaugh, Robert and Trenti, Michele and Vulcani, Benedetta and Wang, Lifan and Wang, Xin and Windhorst, Rogier and Yang, Lilan}, biburl = {https://www.bibsonomy.org/bibtex/2cb53b77d922dccf0562fc8567a3ac96d/gpkulkarni}, description = {A shot in the Dark (Ages): a faint galaxy at $z=9.76$ confirmed with JWST}, interhash = {f6834fc7d534d41561ff171e7c48296b}, intrahash = {cb53b77d922dccf0562fc8567a3ac96d}, keywords = {library}, note = {cite arxiv:2210.15639Comment: Submitted to Nature. 34 pages, 4 main figures, 1 supplementary figure, 2 supplementary tables. Comments are welcome}, timestamp = {2022-10-28T14:17:50.000+0200}, title = {A shot in the Dark (Ages): a faint galaxy at $z=9.76$ confirmed with JWST}, url = {http://arxiv.org/abs/2210.15639}, year = 2022 }