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PUBLICATIONS
FEATURED RESEARCH ARTICLES
Igor Andreoni, Michael W. Coughlin, Daniel A. Perley, Yuhan Yao, Wenbin Lu, S. Bradley Cenko, Harsh Kumar, Shreya Anand, Anna Y. Q. Ho, Mansi M. Kasliwal, Antonio de Ugarte Postigo, Ana Sagu{\'e}s-Carracedo, Steve Schulze, D. Alexander Kann, S. R. Kulkarni, Jesper Sollerman, Nial Tanvir, Armin Rest, Luca Izzo, Jean J. Somalwar, David L. Kaplan, Tom{\'a}s Ahumada, G. C. Anupama, Katie Auchettl, Sudhanshu Barway, Eric C. Bellm, Varun Bhalerao, Joshua S. Bloom, Michael Bremer, Mattia Bulla, Eric Burns, Sergio Campana, Poonam Chandra, Panos Charalampopoulos, Jeff Cooke, Valerio D'Elia, Kaustav Kashyap Das, Dougal Dobie, José Feliciano Agüí Fernández, James Freeburn, Cristoffer Fremling, Suvi Gezari, Simon Goode, Matthew Graham, Erica Hammerstein, Viraj R. Karambelkar, Charles D. Kilpatrick, Erik C. Kool, Melanie Krips, Russ R. Laher, Giorgos Leloudas, Andrew Levan, Michael J. Lundquist, Ashish~A.~Mahabal, Michael S. Medford, M. Coleman Miller, Anais Möller, Kunal Mooley, A. J. Nayana, Guy Nir, Peter T. H. Pang, Emmy Paraskeva, Richard A. Perley, Glen Petitpas, Miika Pursiainen, Vikram Ravi, Ryan Ridden-Harper, Reed Riddle, Mickael Rigault, Antonio C. Rodriguez, Ben Rusholme, Yashvi Sharma, I. A. Smith, Robert D. Stein, Christina Thöne, Aaron Tohuvavohu, Frank Valdes, Jan van Roestel, Susanna D. Vergani, Qinan Wang, Jielai Zhang
A very luminous jet from the disruption of a star by a massive black hole
Image credit: Zwicky Transient Facility/R.Hurt (Caltech/IPAC)
Enabling Kilonova Science with Nancy Grace Roman Space Telescope
Igor Andreoni, Michael Coughlin, Alexander Criswell, Mattia Bulla, Andrew Toivonen, Leo Singer, Antonella Palmese, Eric Burns, Suvi Gezari, Mansi Kasliwal, Weizmann Kiendrebeogo, Ashish Mahabal, Takashi Moriya, Armin Rest, Dan Scolnic, Robert Simcoe, Jamie Soon, Robert Stein, Tony Travouillon
Nancy Grace Roman Space Telescope will have a field of view more than 100 times larger than Hubble. In this paper, we investigated how observations can be optimized to use Roman to find kilonovae, the elusive optical and infrared counterparts to gravitational waves that are produced when a neutron star merges with a companion neutron star or black hole.
In this figure we plotted the Roman 6x3 detectors array over the localization skymap of a binary neutron star merger.
Target of Opportunity Observations of Gravitational Wave Events
with Vera Rubin Observatory
Igor Andreoni, Raffaella Margutti, Om Sharan Salafia, B. Parazin, V. Ashley Villar, Michael W. Coughlin, Peter Yoachim, Kris Mortensen, Daniel Brethauer, S. J. Smartt, Mansi M. Kasliwal, Kate D. Alexander, Shreya Anand, E. Berger, Maria Grazia Bernardini, Federica B. Bianco, Peter K. Blanchard, Joshua S. Bloom, Enzo Brocato, Mattia Bulla, Regis Cartier, S. Bradley Cenko, Ryan Chornock, Christopher M. Copperwheat, Alessandra Corsi, Filippo D'Ammando, Paolo D'Avanzo, Laurence Elise Helene Datrier, Ryan J. Foley, Giancarlo Ghirlanda, Ariel Goobar, Jonathan Grindlay, Aprajita Hajela, Daniel E. Holz, E. C. Kool, Gavin P. Lamb, Tanmoy Laskar, Andrew Levan, Kate Maguire, Morgan May, Andrea Melandri, Dan Milisavljevic, A. A. Miller, Matt Nicholl, Antonella Palmese, Silvia Piranomonte, Armin Rest, Ana Sagues-Carracedo, Karelle Siellez, Leo P. Singer, Mathew Smith, D. Steeghs, and Nial Tanvir
How should we use the Vera C. Rubin Observatory to respond to gravitational wave triggers?
Target of opportunity observations need the right strategy to make discovery possible.
Igor Andreoni, Michael W. Coughlin, Mouza Almualla, Eric C. Bellm, Federica B. Bianco, Mattia Bulla, Antonino Cucchiara, Tim Dietrich, Ariel Goobar, Erik C. Kool, Xiaolong Li, Fabio Ragosta, Ana Agues-Carracedo, Leo P. Singer
We explore expectations for the Vera C. Rubin Observatory to find rare kilonovae during its wide, fast, deep survey of the sky.
What cadence and which filters should be preferred to maximize the discovery of such interesting but elusive transients?
Optimizing Cadences with Realistic Light Curve Filtering for Serendipitous Kilonova Discovery with Vera Rubin Observatory
Fast-transient Searches in Real Time with ZTFReST: Identification of Three Optically-discovered Gamma-ray Burst Afterglows and New Constraints on the Kilonova Rate
Igor Andreoni, Michael W. Coughlin, Erik C. Kool, Mansi M. Kasliwal, Harsh Kumar, Varun Bhalerao, Ana Sagues Carracedo, Anna Y. Q. Ho, Peter T. H. Pang, Divita Saraogi, Kritti Sharma, Vedant Shenoy, Eric Burns, Tomas Ahumada, Shreya Anand, Leo P. Singer, Daniel A. Perley, Kishalay De, U.C. Fremling, Eric C. Bellm, Mattia Bulla, Arien Crellin-Quick, Tim Dietrich, Andrew Drake, Dmitry A. Duev, Ariel Goobar, Matthew J. Graham, David L. Kaplan, S. R. Kulkarni, Russ R. Laher, Ashish A. Mahabal, David L. Shupe, Jesper Sollerman, Richard Walters, and Yuhan Yao
Thanks to ZTFReST we can discover fast transients in optical survey data even without gravitational-wave or gamma-ray burst triggers!
In the first few months of operations, ZTFReST has identified fast and rare sources such as cosmological afterglows and supernova shock breakouts
Constraining the Kilonova Rate with Zwicky Transient Facility Searches Independent of Gravitational Wave and Short Gamma-ray Burst Triggers
Igor Andreoni, Erik C. Kool, Ana Sagues Carracedo, Mansi M. Kasliwal, Mattia Bulla, Tomas Ahumada, Michael W. Coughlin, Shreya Anand, Jesper Sollerman, Ariel Goobar, David L. Kaplan, Tegan T. Loveridge, Viraj Karambelkar, Jeff Cooke, Ashot Bagdasaryan, Eric C. Bellm, S. Bradley Cenko, David O. Cook, Kishalay De, Richard Dekany, Alexandre Delacroix, Andrew Drake, Dmitry A. Duev, Christoffer Fremling, V. Zach Golkhou, Matthew J. Graham, David Hale, S. R. Kulkarni, Thomas Kupfer, Russ R. Laher, Ashish A. Mahabal, Frank J. Masci, Ben Rusholme, Roger M. Smith, Anastasios Tzanidakis, Angela Van Sistine, Yuhan Yao
We constrained the kilonova rate in the nearby Universe with ZTF. In this figure, we compare the ZTF upper limit for GW170817-like kilonovae with results from other optical surveys and with the neutron star merger rate calculated from the observations of gravitational waves, short gamma-ray bursts, Galactic double neutron-star systems, and via population synthesis.
*The figure above is an up-to-date version published in Andreoni & Coughlin et al. (2021)
Zwicky Transient Facility Constraints on the Optical Emission from the Nearby Repeating FRB 180916.J0158+65
Andreoni, Igor; Lu, Wenbin; Smith, Roger M.; Masci, Frank J.; Bellm, Eric C.; Graham, Matthew J.; Kaplan, David L.; Kasliwal, Mansi M.; Kaye, Stephen; Kupfer, Thomas; Laher, Russ R.; Mahabal, Ashish A.; Nordin, Jakob; Porter, Michael; Prince, Thomas A.; Reiley, Dan; Riddle, Reed; Van Roestel, Joannes; Yao, Yuhan
Figure: ZTF observations of a nearby, periodic FRB source.
Probing the extragalactic fast transient sky at minute time-scales with DECam
Andreoni, Igor; Cooke, Jeff; Webb, Sara; Rest, Armin; Pritchard, Tyler; Caleb, Manisha; Chang, Seo-Won.; Farah, Wael; Lien, Amy; Möller, Anais; Ravasio, Maria E.; Abbott, Timothy M. C.; Bhandari, Shivani; Cucchiara, Antonino; Flynn, Chris; Jankowski, Fabian; Keane, Evan F.; Moriya, Takashi J.; Onken, Chris A.; Parthasarathy, Aditya; Price, Daniel C.; Petroff, Emily; Ryder, Stuart; Vohl, Dany; Wolf, Christian
Figures: Light curve of a fast optical transient candidate (note that the abscissa is in minutes!). Plot of the 3D phase space probed with DECam during the Deeper Wider Faster program.
GROWTH on S190814bv: Deep Synoptic Limits on the Optical/Near-infrared Counterpart to a Neutron Star─Black Hole Merger
Andreoni, Igor; Goldstein, Daniel A.; Kasliwal, Mansi M.; Nugent, Peter E.; Zhou, Rongpu; Newman, Jeffrey A.; Bulla, Mattia; Foucart, Francois; Hotokezaka, Kenta; Nakar, Ehud; Nissanke, Samaya; Raaijmakers, Geert; Bloom, Joshua S.; De, Kishalay; Jencson, Jacob E.; Ward, Charlotte; Ahumada, Tomás; Anand, Shreya; Buckley, David A. H.; Caballero-García, Maria D. Castro-Tirado, Alberto J.; Copperwheat, Christopher M.; Coughlin, Michael W.; Cenko, S. Bradley; Gromadzki, Mariusz; Hu, Youdong; Karambelkar, Viraj R.; Perley, Daniel A.; Sharma, Yashvi; Valeev, Azamat F.; Cook, David O.; Fremling, U. Christoffer; Kumar, Harsh; Taggart, Kirsty; Bagdasaryan, Ashot; Cooke, Jeff; Dahiwale, Aishwarya; Dhawan, Suhail; Dobie, Dougal; Gatkine, Pradip; Golkhou, V. Zach; Goobar, Ariel; Chaves, Andreas Guerra; Hankins, Matthew; Kaplan, David L.; Kong, Albert K. H.; Kool, Erik C.; Mohite, Siddharth; Sollerman, Jesper; Tzanidakis, Anastasios; Webb, Sara; Zhang, Keming
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Upper figure: The ejecta mass and viewing angle parameter space of GW190814 was constrained with DECam optical observations.
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Left figure: Constraints on the parameter space of a
black hole-neutron star binary
progenitor of GW190814
GROWTH on S190510g: DECam Observation Planning and Follow-up of a Distant Binary Neutron Star Merger Candidate
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Andreoni, Igor; Goldstein, Daniel A.; Anand, Shreya; Coughlin, Michael W.; Singer, Leo P.; Ahumada, Tomás; Medford, Michael; Kool, Erik C.; Webb, Sara; Bulla, Mattia; Bloom, Joshua S.; Kasliwal, Mansi M.; Nugent, Peter E.; Bagdasaryan, Ashot; Barnes, Jennifer; Cook, David O.; Cooke, Jeff; Duev, Dmitry A.; Fremling, U. Christoffer; Gatkine, Pradip Golkhou, V. Zach; Kong, Albert K. H.; Mahabal, Ashish; Martínez-Palomera, Jorge; Tao, Duo; Zhang, Keming
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Upper figure: The refined skymap of the S190510g gravitational wave event, with the circles representing the DECam observations that we performed.
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Left figure: Triangles indicate the observational constraints that we placed on transient emission like GW170817.
A strategy for LSST to unveil a population of kilonovae without gravitational-wave triggers
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Andreoni, Igor; Anand, Shreya; Bianco, Federica B.; Cenko, Brad; Cowperthwaite, Philip; Coughlin, Michael W.; Drout, Maria; Golkhou, V. Zach; Kaplan, David; Mooley, Kunal P.; Pritchard, Tyler A.;
Singer, Leo P.; Webb, Sara
Figure: Light curve of the kilonova associated with the gravitational-wave event GW170817 sampled as if it was observed with LSST using the proposed cadence strategy.
Follow Up of GW170817 and Its Electromagnetic Counterpart
by Australian-Led Observing Programmes
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Andreoni, I.; Ackley, K.; Cooke, J.; Acharyya, A.; Allison, J. R.; Anderson, G. E.; Ashley, M. C. B.; Baade, D.; Bailes, M.; Bannister, K.; Beardsley, A.; Bessell, M. S.; Bian, F.; Bland, P. A.; Boer, M.; Booler, T.; Brandeker, A.; Brown, I. S.; Buckley, D. A. H.; Chang, S. -W. Coward, D. M.; Crawford, S.; Crisp, H.; Crosse, B.; Cucchiara, A.; Cupák, M.; de Gois, J. S.; Deller, A.; Devillepoix, H. A. R.; Dobie, D.; Elmer, E.; Emrich, D.; Farah, W.; Farrell, T. J.; Franzen, T.; Gaensler, B. M.; Galloway, D. K.; Gendre, B.; Giblin, T.; Goobar, A.; Green, J.; Hancock, P. J.; Hartig, B. A. D.; Howell, E. J.; Horsley, L.; Hotan, A.; Howie, R. M.; Hu, L.; Hu, Y.; James, C. W.; Johnston, S.; Johnston-Hollitt, M.; Kaplan, D. L.; Kasliwal, M.; Keane, E. F.; Kenney, D.; Klotz, A.; Lau, R.; Laugier, R.; Lenc, E.; Li, X.; Liang, E.; Lidman, C.; Luvaul, L. C.; Lynch, C.; Ma, B.; Macpherson, D.; Mao, J.; McClelland, D. E.; McCully, C.; Möller, A.; Morales, M. F.; Morris, D.; Murphy, T.; Noysena, K.; Onken, C. A.; Orange, N. B.; OsÅ‚owski, S.; Pallot, D.; Paxman, J.; Potter, S. B.; Pritchard, T.; Raja, W.; Ridden-Harper, R.; Romero-Colmenero, E.; Sadler, E. M.; Sansom, E. K.; Scalzo, R. A.; Schmidt, B. P.; Scott, S. M.; Seghouani, N.; Shang, Z.; Shannon, R. M.; Shao, L.; Shara, M. M.; Sharp, R.; Sokolowski, M.; Sollerman, J.; Staff, J.; Steele, K.; Sun, T.; Suntzeff, N. B.; Tao, C.; Tingay, S.; Towner, M. C.; Thierry, P.; Trott, C.; Tucker, B. E.; Väisänen, P.; Krishnan, V. Venkatraman; Walker, M.; Wang, L.; Wang, X.; Wayth, R.; Whiting, M.; Williams, A.; Williams, T.; Wolf, C.; Wu, C.; Wu, X.; Yang, J.; Yuan, X.; Zhang, H.; Zhou, J.; Zovaro, H.
Figures: Detection image, rapidly-reddening spectra, and light curve of the GW170817 kilonova, the first discovered optical counterpart to a gravitational-wave signal. The Australian astronomical community teamed up to collect a rich dataset, including optical/near-infrared imaging and spectroscopy, radio imaging, and searches for fast radio bursts.
Mary, a Pipeline to Aid Discovery of Optical Transients
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Andreoni, I.; Jacobs, C.; Hegarty, S.; Pritchard, T.; Cooke, J.; Ryder, S.
Figures: The Mary pipeline uses image subtraction to unveil transient and variable sources (top figure). Supernovae in distant galaxies (right figure) can be discovered with this technique, by subtracting the reference image the science image. The Mary pipeline was designed to work on DECam images, but we used it also for images taken with the Hyper-Suprime Cam mounted on the 8.2-m Subaru telescope.
A time domain experiment with Swift: monitoring of seven nearby galaxies
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Andreoni, I.; D'Avanzo, P.; Campana, S.; Branchesi, M.; Bernardini, M. G.; Della Valle, M.; Mannucci, F.; Melandri, A.; Tagliaferri, G.
Figures: We monitored seven nearby galaxies with the Neil Gehrels Swift Observatory searching for supernova shock breakouts, bright flashes generated by the collapse of massive stars. These images show our galaxy sample as observed in the X-rays (left) and in the UltraViolet (right).
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