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2019 Workshop Stellar deaths and their afterlives are laboratories that test fundamental physics through astrophysics. The advent of extremely wide‐field surveys will revolutionize this field, and we will be able to probe new time and energy scales. The community will need to build new infrastructure and change existing paradigms to maximize the science return of these facilities. This workshop will connect scientists with expertise in multi‐ messenger astrophysics with statisticians, data scientists, and software developers. Together, they will highlight what infrastructure exists, identify how these pieces may be connected together into a larger ecosystem, and develop a roadmap to prepare for future surveys. Agenda AGENDA Thursday, April 25, 2019 8:00 – 9:00 AM Registration/Breakfast Lobby/Café Azafran 9:00 Welcome Nancy Levenson, Deputy Director, STScI Chair: Gautham CHALLENGES FACING TIME‐DOMAIN Narayan ASTROPHYSICS 9:15 Iair Arcavi Coordinating Followup of GW Events 9:30 Arfon Smith MAST Archive and Operations in the MMA Era. 9:45 Saurabh Jha Multi‐Messenger Astrophysics: We Are The Messengers 10:00 10:15 10:30 – 11:00 AM AM Coffee Break Café Azafran Chair: Renée Hložek DATA SCIENCE AND MACHINE LEARNING FOR MMA 11:00 Emilie Ishida Human in the Loop: Adaptive Learning in Astronomy 11:15 Wolfgang Kerzendorf DALEK ‐ Supernova Physics Meets Machine Learning 11:30 Victor Francisco Ksoll Characterizing Extragalactic Pre‐Main‐Sequence Stars with Machine and Deep Learning Techniques 11:45 Daniel Muthukrishna RAPID: Early Classification of Explosive Transients using Deep Learning 12:00 Darryl Wright Supporting Transient Surveys with Citizen Science 12:15 Kyle Rocha Using Machine Learning to Predict Outcomes for Binary Stellar Evolution 12:30 – 2:00 PM Lunch/Posters Chair: Massimo PUTTING THE MULTI IN MULTI‐MESSENGER Robberto 2:00 Jennifer Lotz GEMMA: Gemini in the Era of Multi‐Messenger Astronomy 2:15 Eric Burns Joint Gravitational Wave and Gamma‐ray Burst Online Searches 2:30 Jeff Cooke The Deeper, Wider, Faster Program: Pioneering Multi‐facility, Multi‐wavelength, Multi‐messenger Fast Transient Exploration 2:45 Michael Coughlin Finding LISA Gravitational‐wave Sources in the Optical Time Domain 3:00 Azadeh Keivani Multi‐messenger Gravitational‐Wave + High‐Energy Neutrino Searches 3:15 Group Photo Front Steps of Muller Building 3:30 – 4:00 PM PM Coffee Break Café Azafran Chair: Federica Bianco BROKERS, TOMS, AND DATA HUBS 4:00 Dave Coulter Software Platforms to Enhance Decision Making for Multi‐Messenger Astronomy 4:15 Francisco Forster The Universe in a Stream: Challenges and Progress of the ALeRCE Broker 4:30 Monika Soraisam ANTARES: Brokering Alerts in Real‐time in the Big‐ Data Era 4:45 Rachel Street Microlensing as a Case Study of Alert‐based Science and Technologies 5:00 Ken Smith Lasair: The Transient Alert Broker for LSST:UK 5:30 – 7:00 PM Welcome Reception Café Azafran 7:00 PM Dinner Various *Talk Times: Invited Speakers 15 + 2 Contributing Speakers 10 + 2 Friday, April 26, 2016 8:15 – 9:00 AM Registration/Breakfast Café Azafran Chair: Ivelina DATABASES AND ARCHIVES Momcheva 9:00 Melissa Graham The LSST Data Management Systems: Infrastructures for EMMA 9:15 Dmitry Duev The Zwicky Transient Facility (ZTF) Data Ecosystem 9:30 Jan‐Uwe Ness Multi‐mission Coordinations 9:45 Kyle Chard Parsl, a Python‐based Parallel Scripting Library 10:00 Jamie Kinney From Zero to ML ‐ Managing and Analyzing Astronomy Data on Google Cloud 10:30 – 11:00 AM AM Coffee Break Café Azafran Chair: Leo Singer MULTI‐MESSENGER P2 11:00 John Graham Limitations on IMF Variability as a Function of Metallicity 11:15 Kshitij Aggarwal Finding Fast Radio Bursts with Realfast at the VLA 11:30 Carl‐Johann Haster Gravitational Waves as a Piece of the Astrophysical Multi‐messenger Puzzle 11:45 Joshua Schleider Nimble: A Mission Concept for Gravitational Wave Counterpart Astrophysics 12:00 Nao Suzuki HSC Transient Survey 12:15 Ann Hornschemeier Stellar‐origin Black Holes and Neutron Stars in the 2020’s and Beyond: The Post Chandra and XMM‐ Newton Era 12:30 – 2:00 PM Lunch/Posters Chair: Ryan Foley FOLLOWUP STRATEGY AND INSTRUMENTATION 2:00 Alexander van der Probing the Transient Sky with SCORPIO Horst 2:15 Morten Anderson Gemini in LSST/SCORPIO Era 2:30 Igor Andreoni ZTF and DECam Follow‐up of Neutron Star Mergers during O3 2:45 Aaron Tohuvavohu Swift in the Multi‐messenger Era 3:00 David Cook The Role of NED in Identifying EM Counterparts to GW Events 3:15 Sarah Burke‐Spoalar MMA in the Nanohertz Gravitational Wave‐band 3:30 – 4:00 PM Coffee Café Azafran Chair: Armin Rest DISCUSSION 4:00 – 5:00 PM Workshop Adjourns *Talk Times: Invited Speakers 15 + 2 Contributing Speakers 10 + 2 Talk Abstracts Kshitij Aggarwal (West Virginia University) Realfast: Real‐time, Commensal Fast Transient Search at the Very Large Array Localization of a Fast Radio Burst (FRB) to ~arcsecond precision is necessary for confident host association, and is likely to prove essential to studying FRB environments, host electron densities, the structure and fields of intervening media. The Realfast commensal FRB detection system on the Karl G. Jansky Very Large Array (VLA) will detect and precisely localize FRBs in real time by performing fast imaging (~5ms) of dedispersed data. In late 2016, Realfast performed the first FRB localization, pinning down the repeating FRB121102 to a precision of 0.2”, which enabled the identification of its host and further studies of its environment. This talk will review the current status and ongoing development of the commensal Realfast system. This will include results from the observing run using the prototype (non‐commensal, CPU‐based) system, insights into the unique issues and benefits of imaging searches, and the use of machine learning techniques to cluster and classify the vast amount of candidates expected from this pipeline. Morten Andersen (Gemini Observatory) Gemini in LSST/SCORPIO Era The advent of LSST will dramatically alter the approach to observe newly discovered transient objects. Gemini is currently in the process of building the SCORPIO instrument that will be very well suited for rapid followup observations. Gemini further have rapid target of opportunity capabilities to take advantage take advantage of triggers from the community. However the system will have to change to cope with the expected rate of triggers in the near future. Here we present both briefly the SCORPIO instrument as well as Geminis plans in collaboration with other observatories in in the future to handle numerous triggers from the community. Igor Andreoni (Caltech) ZTF and DECam Follow‐up of Neutron Star Mergers during O3 After GW170817, we are looking forward to the next binary neutron star merger detection and the very first neutron star – black hole merger. Both types of merger are expected to generate a transient called kilonova, observable at optical/infrared wavelengths. The GROWTH collaboration can count on major facilities for discovery, characterization, and monitoring of gravitational‐wave counterparts. In particular, the Zwicky Transient Facility (ZTF) at Palomar and the Dark Energy Camera (DECam) at CTIO are wide‐field instruments perfectly placed to discover faint kilonovae shortly after gravitational‐wave triggers are issued. I will present our plans for kilonova discovery with ZTF and DECam, touching on rapid transient detection techniques and infrastructure. Iair Arcavi (Tel Aviv University) Coordinating Followup of GW Events As we enter the era of the first NS merger samples, we need to better coordinate our search for EM counterparts. The early (first hours ‐ day) emission of such counterparts turns out to be crucial for distinguishing between models of the ejecta structure and properties, and the merger physics. Localizations will still be as large (or larger) than in the GW170817 case, and the amount of observing time devoted to that event is not sustainable in the sample era. We must be more efficient with our telescopes. We should therefore design and build a system for coordinating observations between groups to avoid duplication, maximize our coverage of the localization region as quickly as possible, and divide vetting and followup chores of identified candidates. I will present some ideas on how to start doing this, based on similar systems I developed for coordinating followup of supernovae and tidal disruption events in large collaborations. Sarah Burke‐Spolaor (West Virginia University) MMA in the Nanohertz Gravitational Wave‐band Pulsar timing arrays are already placing limits on the evolution of binary supermassive black holes in galaxy mergers, and in the near future should begin to detect these objects. I will discuss the prospects of, methods for, and good practices for multi‐messenger detection of these objects with Pulsar Timing Arrays and other electromagnetic observatories. Eric Burns (NASA Goddard) Joint Gravitational Wave and Gamma‐ray Burst Online Searches The Fermi Gamma‐ray Burst Monitor team and the LIGO and Virgo Collaborations are working together to automatically associate and localize neutron star mergers in real‐time starting with the O3 observing run. Overall this promises to increase the number of gravitational wave signals reported in real‐time and to shrink the localization regions available shortly after merger time. These events and joint localizations will be reported to the follow‐up community. We will discuss what is being done, the expected improvements, what follow‐up observers need to know, and prospects for future improvements. David Cook (IPAC/Caltech) The Role of NED in Identifying EM Counterparts to GW Events The detection of gravitational waves (GWs) has opened a new window into the Universe by enabling direct studies of mergers of massive, compact objects. Some of the largest impacts on our understanding of these events will come when combining the GW data with their electromagnetic (EM) counterparts. However, due to the large area (> 100 deg^2) localization of LIGO events, identifying their correct EM counterparts is no small feat and is akin to finding a needle in a haystack.
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