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6 results on '"Muller-Bravo, Tomas E."'

1. The Einstein Probe transient EP240414a: Linking Fast X-ray Transients, Gamma-ray Bursts and Luminous Fast Blue Optical Transients

Author

van Dalen, Joyce N. D., Levan, Andrew J., Jonker, Peter G., Malesani, Daniele B., Izzo, Luca, Sarin, Nikhil, Quirola-Vásquez, Jonathan, Sánchez, Daniel Mata, Postigo, Antonio de Ugarte, van Hoof, Agnes P. C., Torres, Manuel A. P., Schulze, Steve, Littlefair, Stuart P., Chrimes, Ashley, Ravasio, Maria E., Bauer, Franz E., Martin-Carrillo, Antonio, Fraser, Morgan, van der Horst, Alexander J., Jakobsson, Pall, O'Brien, Paul, De Pasquale, Massimiliano, Pugliese, Giovanna, Sollerman, Jesper, Tanvir, Nial R., Zafar, Tayyaba, Anderson, Joseph P., Galbany, Lluís, Gal-Yam, Avishay, Gromadzki, Mariusz, Muller-Bravo, Tomas E., Ragosta, Fabio, and Terwel, Jacco H.

Subjects
Astrophysics - High Energy Astrophysical Phenomena
Abstract

Detections of fast X-ray transients (FXTs) have been accrued over the last few decades. However, their origin has remained mysterious. There is now rapid progress thanks to timely discoveries and localisations with the Einstein Probe mission. Early results indicate that FXTs may frequently, but not always, be associated with gamma-ray bursts (GRBs). Here, we report on the multi-wavelength counterpart of FXT EP240414a, which has no reported gamma-ray counterpart. The transient is located 25.7~kpc in projection from a massive galaxy at $z=0.40$. We perform comprehensive photometric and spectroscopic follow-up. The optical light curve shows at least three distinct emission episodes with timescales of $\sim 1, 4$ and 15 days and peak absolute magnitudes of $M_R \sim -20$, $-21$, and $-19.5$, respectively. The optical spectrum at early times is extremely blue, inconsistent with afterglow emission. It may arise from the interaction of both jet and supernova shock waves with the stellar envelope and a dense circumstellar medium, as has been suggested for some Fast Blue Optical Transients (LFBOTs). At late times, the spectrum evolves to a broad-lined~Type~Ic supernova, similar to those seen in collapsar long-GRBs. This implies that the progenitor of EP240414a is a massive star creating a jet-forming supernova inside a dense envelope, resulting in an X-ray outburst with a luminosity of $\sim 10^{48}$ erg s$^{-1}$, and the complex observed optical/IR light curves. If correct, this argues for a causal link between the progenitors of long-GRBs, FXTs and LFBOTs., Comment: 36 pages, 13 figures, submitted to ApJ

Published
2024

2. SN 2022acko: the First Early Far-Ultraviolet Spectra of a Type IIP Supernova

Author

Bostroem, K. Azalee, Dessart, Luc, Hillier, D. John, Lundquist, Michael, Andrews, Jennifer E., Sand, David J., Dong, Yize, Valenti, Stefano, Haislip, Joshua, Hoang, Emily T., Hosseinzadeh, Griffin, Janzen, Daryl, Jencson, Jacob E., Jha, Saurabh W., Kouprianov, Vladimir, Pearson, Jeniveve, Retamal, Nicolas E. Meza, Reichart, Daniel E., Shrestha, Manisha, Ashall, Christopher, Baron, E., Brown, Peter J., DerKacy, James M., Farah, Joseph, Galbany, Lluis, Hernandez, Jonay I. Gonzalez, Green, Elizabeth, Hoeflich, Peter, Howell, D. Andrew, Kwok, Lindsey A., McCully, Curtis, Muller-Bravo, Tomas E., Newsome, Megan, Gonzalez, Estefania Padilla, Pellegrino, Craig, Rho, Jeonghee, Rowe, Micalyn, Schwab, Michaela, Shahbandeh, Melissa, Smith, Nathan, Strader, Jay, Terreran, Giacomo, Van Dyk, Schuyler D., and Wyatt, Samuel

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Solar and Stellar Astrophysics
Abstract

We present five far- and near-ultraviolet spectra of the Type II plateau supernova, SN 2022acko, obtained 5, 6, 7, 19, and 21 days after explosion, all observed with the Hubble Space Telescope/Space Telescope Imaging Spectrograph. The first three epochs are earlier than any Type II plateau supernova has been observed in the far-ultraviolet revealing unprecedented characteristics. These three spectra are dominated by strong lines, primarily from metals, which contrasts with the relatively featureless early optical spectra. The flux decreases over the initial time series as the ejecta cools and line-blanketing takes effect. We model this unique dataset with the non-local thermodynamic equilibrium radiation transport code CMFGEN, finding a good match to the explosion of a low mass red supergiant with energy Ekin = 6 x 10^50 erg. With these models we identify, for the first time, the ions that dominate the early UV spectra. We also present optical photometry and spectroscopy, showing that SN 2022acko has a peak absolute magnitude of V = -15.4 mag and plateau length of ~115d. The spectra closely resemble those of SN 2005cs and SN 2012A. Using the combined optical and UV spectra, we report the fraction of flux redwards of the uvw2, U, B, and V filters on days 5, 7, and 19. We also create a spectral time-series of Type II supernovae in the ultraviolet, demonstrating the rapid decline of UV flux over the first few weeks of evolution. Future observations of Type II supernovae will continue to explore the diversity seen in the limited set of high-quality UV spectra., Comment: Published in ApJL

Published
2023
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3. SN 2019hcc: A Type II Supernova Displaying Early O II Lines

Author

Parrag, Eleonora, Inserra, Cosimo, Schulze, Steve, Anderson, Joseph, Chen, Ting-Wan, Leloudas, Giorgios, Galbany, Lluis, Gutierrez, Claudia P., Hiramatsu, Daichi, Kankare, Erkki, Muller-Bravo, Tomas E., Nicholl, Matt, Pignata, Giuliano, Cartier, Regis, Gromadzki, Mariusz, Kozyreva, Alexandra, Rau, Arne, Burke, Jamison, Howell, D. Andrew, McCully, Curtis, and Pellegrino, Craig

Subjects
Astrophysics - High Energy Astrophysical Phenomena, Astrophysics - Solar and Stellar Astrophysics
Abstract

We present optical spectroscopy together with ultraviolet, optical and near-infrared photometry of SN 2019hcc, which resides in a host galaxy at redshift 0.044, displaying a sub-solar metallicity. The supernova spectrum near peak epoch shows a `w' shape at around 4000 {\AA} which is usually associated with O II lines and is typical of Type I superluminous supernovae. SN 2019hcc post-peak spectra show a well-developed H alpha P-Cygni profile from 19 days past maximum and its light curve, in terms of its absolute peak luminosity and evolution, resembles that of a fast-declining Hydrogen-rich supernova (SN IIL). The object does not show any unambiguous sign of interaction as there is no evidence of narrow lines in the spectra or undulations in the light curve. Our tardis spectral modelling of the first spectrum shows that Carbon, Nitrogen and Oxygen (CNO) at 19000 K reproduce the `w' shape and suggests that a combination of non-thermally excited CNO and metal lines at 8000 K could reproduce the feature seen at 4000 {\AA}. The Bolometric light curve modelling reveals that SN 2019hcc could be fit with a magnetar model, showing a relatively strong magnetic field (B > 3 x 10^14 G), which matches the peak luminosity and rise time without powering up the light curve to superluminous luminosities. The high-energy photons produced by the magnetar would then be responsible for the detected O II lines. As a consequence, SN 2019hcc shows that a `w' shape profile at around 4000 {\AA}, usually attributed to O II, is not only shown in superluminous supernovae and hence it should not be treated as the sole evidence of the belonging to such a supernova type., Comment: Paper accepted on MNRAS, 24 pages, 18 figures

Published
2021
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4. Revealing the Progenitor of SN 2021zby through Analysis of the TESS Shock-cooling Light Curve

Author

Wang, Qinan, Armstrong, Patrick, Zenati, Yossef, Ridden-Harper, Ryan, Rest, Armin, Arcavi, Iair, Kilpatrick, Charles D., Foley, Ryan J., Tucker, Brad E., Lidman, Chris, Killestein, Thomas L., Shahbandeh, Melissa, Anderson, Joseph P., Angulo, Rodrigo, Ashall, Chris, Burke, Jamison, Chen, Ting-Wan, von Coelln, Sophie, Dalrymple, Kyle A., Davis, Kyle W., Fulton, Michael D., Galbany, Lluis, Gonzalez, Estefania Padilla, Gao, Bore, Gromadzki, Mariusz, Howell, D. Andrew, Ihanec, Nada, Jencson, Jacob E., Jones, David O., Lyman, Joseph D., McCully, Curtis, Muller-Bravo, Tomas E., Newsome, Megan, Nicholl, Matt, O'Neill, David, Pellegrino, Craig, Rest, Sofia, Smartt, Stephen J., Smith, Ken, Srivastav, Shubham, Terreran, Giacomo, Tinyanont, Samaporn, Young, David R., Zenteno, Alfredo, Wang, Qinan, Armstrong, Patrick, Zenati, Yossef, Ridden-Harper, Ryan, Rest, Armin, Arcavi, Iair, Kilpatrick, Charles D., Foley, Ryan J., Tucker, Brad E., Lidman, Chris, Killestein, Thomas L., Shahbandeh, Melissa, Anderson, Joseph P., Angulo, Rodrigo, Ashall, Chris, Burke, Jamison, Chen, Ting-Wan, von Coelln, Sophie, Dalrymple, Kyle A., Davis, Kyle W., Fulton, Michael D., Galbany, Lluis, Gonzalez, Estefania Padilla, Gao, Bore, Gromadzki, Mariusz, Howell, D. Andrew, Ihanec, Nada, Jencson, Jacob E., Jones, David O., Lyman, Joseph D., McCully, Curtis, Muller-Bravo, Tomas E., Newsome, Megan, Nicholl, Matt, O'Neill, David, Pellegrino, Craig, Rest, Sofia, Smartt, Stephen J., Smith, Ken, Srivastav, Shubham, Terreran, Giacomo, Tinyanont, Samaporn, Young, David R., and Zenteno, Alfredo

Abstract

We present early observations and analysis of the double-peaked Type IIb supernova (SN IIb) SN 2021zby. TESS captured the prominent early shock-cooling peak of SN 2021zby within the first similar to 10 days after explosion with a 30 minute cadence. We present optical and near-infrared spectral series of SN 2021zby, including three spectra during the shock-cooling phase. Using a multiband model fit, we find that the inferred properties of its progenitor are consistent with a red supergiant or yellow supergiant, with an envelope mass of similar to 0.30-0.65 M-circle dot and an envelope radius of similar to 120-300 R-circle dot. These inferred progenitor properties are similar to those of other SNe IIb with a double-peaked feature, such as SNe 1993J, 2011dh, 2016gkg, and 2017jgh. This study further validates the importance of the high cadence and early coverage in resolving the shape of the shock-cooling light curve, while the multiband observations, particularly UV, are also necessary to fully constrain the progenitor properties.

Published
2023

5. Weak Mass Loss from the Red Supergiant Progenitor of the Type II SN 2021yja

Author

Hosseinzadeh, Griffin, Kilpatrick, Charles D., Dong, Yize, Sand, David J., Andrews, Jennifer E., Bostroem, K. Azalee, Janzen, Daryl, Jencson, Jacob E., Lundquist, Michael, Retamal, Nicolas E. Meza, Pearson, Jeniveve, Valenti, Stefano, Wyatt, Samuel, Burke, Jamison, Hiramatsu, Daichi, Howell, D. Andrew, McCully, Curtis, Newsome, Megan, Gonzalez, Estefania Padilla, Pellegrino, Craig, Terreran, Giacomo, Auchettl, Katie, Davis, Kyle W., Foley, Ryan J., Miao, Hao-Yu, Pan, Yen-Chen, Rest, Armin, Siebert, Matthew R., Taggart, Kirsty, Tucker, Brad E., Leung, Feng Lin Cyrus, Swift, Jonathan J., Yang, Grace, Anderson, Joseph P., Ashall, Chris, Benetti, Stefano, Brown, Peter J., Cartier, Regis, Chen, Ting-Wan, Della Valle, Massimo, Galbany, Lluis, Gomez, Sebastian, Gromadzki, Mariusz, Haislip, Joshua, Hsiao, Eric Y., Inserra, Cosimo, Jha, Saurabh W., Killestein, Thomas L., Kouprianov, Vladimir, Kozyreva, Alexandra, Muller-Bravo, Tomas E., Nicholl, Matt, Paraskeva, Emmy, Reichart, Daniel E., Ryder, Stuart, Shahbandeh, Melissa, Shappee, Ben, Smith, Nathan, Young, David R., Hosseinzadeh, Griffin, Kilpatrick, Charles D., Dong, Yize, Sand, David J., Andrews, Jennifer E., Bostroem, K. Azalee, Janzen, Daryl, Jencson, Jacob E., Lundquist, Michael, Retamal, Nicolas E. Meza, Pearson, Jeniveve, Valenti, Stefano, Wyatt, Samuel, Burke, Jamison, Hiramatsu, Daichi, Howell, D. Andrew, McCully, Curtis, Newsome, Megan, Gonzalez, Estefania Padilla, Pellegrino, Craig, Terreran, Giacomo, Auchettl, Katie, Davis, Kyle W., Foley, Ryan J., Miao, Hao-Yu, Pan, Yen-Chen, Rest, Armin, Siebert, Matthew R., Taggart, Kirsty, Tucker, Brad E., Leung, Feng Lin Cyrus, Swift, Jonathan J., Yang, Grace, Anderson, Joseph P., Ashall, Chris, Benetti, Stefano, Brown, Peter J., Cartier, Regis, Chen, Ting-Wan, Della Valle, Massimo, Galbany, Lluis, Gomez, Sebastian, Gromadzki, Mariusz, Haislip, Joshua, Hsiao, Eric Y., Inserra, Cosimo, Jha, Saurabh W., Killestein, Thomas L., Kouprianov, Vladimir, Kozyreva, Alexandra, Muller-Bravo, Tomas E., Nicholl, Matt, Paraskeva, Emmy, Reichart, Daniel E., Ryder, Stuart, Shahbandeh, Melissa, Shappee, Ben, Smith, Nathan, and Young, David R.

Abstract

We present high-cadence optical, ultraviolet (UV), and near-infrared data of the nearby (D approximate to 23 Mpc) Type II supernova (SN) 2021yja. Many Type II SNe show signs of interaction with circumstellar material (CSM) during the first few days after explosion, implying that their red supergiant (RSG) progenitors experience episodic or eruptive mass loss. However, because it is difficult to discover SNe early, the diversity of CSM configurations in RSGs has not been fully mapped. SN 2021yja, first detected within approximate to 5.4 hours of explosion, shows some signatures of CSM interaction (high UV luminosity and radio and x-ray emission) but without the narrow emission lines or early light-curve peak that can accompany CSM. Here we analyze the densely sampled early light curve and spectral series of this nearby SN to infer the properties of its progenitor and CSM. We find that the most likely progenitor was an RSG with an extended envelope, encompassed by low-density CSM. We also present archival Hubble Space Telescope imaging of the host galaxy of SN 2021yja, which allows us to place a stringent upper limit of less than or similar to 9 M-circle dot; on the progenitor mass. However, this is in tension with some aspects of the SN evolution, which point to a more massive progenitor. Our analysis highlights the need to consider progenitor structure when making inferences about CSM properties, and that a comprehensive view of CSM tracers should be made to give a fuller view of the last years of RSG evolution.

Published
2022
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6. SN 2019ehk: A Double-peaked Ca-rich Transient with Luminous X-Ray Emission and Shock-ionized Spectral Features

Author

Jacobson-Galan, Wynn V., Margutti, Raffaella, Kilpatrick, Charles D., Hiramatsu, Daichi, Perets, Hagai, Khatami, David, Foley, Ryan J., Raymond, John, Yoon, Sung-Chul, Bobrick, Alexey, Zenati, Yossef, Galbany, Lluis, Andrews, Jennifer, Brown, Peter J., Cartier, Regis, Coppejans, Deanne L., Dimitriadis, Georgios, Dobson, Matthew, Hajela, Aprajita, Howell, D. Andrew, Kuncarayakti, Hanindyo, Milisavljevic, Danny, Rahman, Mohammed, Rojas-Bravo, Cesar, Sand, David J., Shepherd, Joel, Smartt, Stephen J., Stacey, Holland, Stroh, Michael, Swift, Jonathan J., Terreran, Giacomo, Vinko, Jozsef, Wang, Xiaofeng, Anderson, Joseph P., Baron, Edward A., Berger, Edo, Blanchard, Peter K., Burke, Jamison, Coulter, David A., DeMarchi, Lindsay, DerKacy, James M., Fremling, Christoffer, Gomez, Sebastian, Gromadzki, Mariusz, Hosseinzadeh, Griffin, Kasen, Daniel, Kriskovics, Levente, McCully, Curtis, Muller-Bravo, Tomas E., Nicholl, Matt, Ordasi, Andras, Pellegrino, Craig, Piro, Anthony L., Pal, Andras, Ren, Juanjuan, Rest, Armin, Rich, R. Michael, Sai, Hanna, Sarneczky, Krisztian, Shen, Ken J., Short, Philip, Siebert, Matthew R., Stauffer, Candice, Szakats, Robert, Zhang, Xinhan, Zhang, Jujia, Zhang, Kaicheng, Jacobson-Galan, Wynn V., Margutti, Raffaella, Kilpatrick, Charles D., Hiramatsu, Daichi, Perets, Hagai, Khatami, David, Foley, Ryan J., Raymond, John, Yoon, Sung-Chul, Bobrick, Alexey, Zenati, Yossef, Galbany, Lluis, Andrews, Jennifer, Brown, Peter J., Cartier, Regis, Coppejans, Deanne L., Dimitriadis, Georgios, Dobson, Matthew, Hajela, Aprajita, Howell, D. Andrew, Kuncarayakti, Hanindyo, Milisavljevic, Danny, Rahman, Mohammed, Rojas-Bravo, Cesar, Sand, David J., Shepherd, Joel, Smartt, Stephen J., Stacey, Holland, Stroh, Michael, Swift, Jonathan J., Terreran, Giacomo, Vinko, Jozsef, Wang, Xiaofeng, Anderson, Joseph P., Baron, Edward A., Berger, Edo, Blanchard, Peter K., Burke, Jamison, Coulter, David A., DeMarchi, Lindsay, DerKacy, James M., Fremling, Christoffer, Gomez, Sebastian, Gromadzki, Mariusz, Hosseinzadeh, Griffin, Kasen, Daniel, Kriskovics, Levente, McCully, Curtis, Muller-Bravo, Tomas E., Nicholl, Matt, Ordasi, Andras, Pellegrino, Craig, Piro, Anthony L., Pal, Andras, Ren, Juanjuan, Rest, Armin, Rich, R. Michael, Sai, Hanna, Sarneczky, Krisztian, Shen, Ken J., Short, Philip, Siebert, Matthew R., Stauffer, Candice, Szakats, Robert, Zhang, Xinhan, Zhang, Jujia, and Zhang, Kaicheng

Abstract

We present panchromatic observations and modeling of the Calcium-rich supernova (SN) 2019ehk in the starforming galaxy M100 (d≃16.2 Mpc) starting 10 hr after explosion and continuing for∼300 days. SN 2019ehk shows a double-peaked optical light curve peaking at tQ=Q3 and 15 days. The first peak is coincident with luminous, rapidly decaying Swift-XRTVdiscovered X-ray emission (Lx≃10 erg s- 41 -1at 3 days Lx∞t.3)

Published
2020

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