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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').

73 results found.

  1. LIGO/Virgo S190426c: Update on Probability of Terrestrial Origin
  2. LIGO/Virgo S190426c: Swift UVOT - no new counterpart candidates identified
  3. LIGO/Virgo S190425z: Swift UVOT - no new sources identified, and a summary of the Swift UVOT processing of GW triggers.
  4. LIGO/Virgo S190426c: NICER X-ray Follow-Up of ZTF19aassfws
  5. LIGO/Virgo S190426c: AMI-LA radio observations of ZTF19aassfws
  6. LIGO/Virgo S190426c: VLA Follow-Up Observations of ZTF19aassfws
  7. LIGO-Virgo S190426c: Pan-STARRS non-detection of ZTF19aassfws
  8. LIGO/Virgo S190426c: Archival VLASS Observations of ZTF19aassfws 14 days prior to Merger
  9. LIGO/Virgo S190426c: Correction to typo in GCN 24433
  10. LIGO/Virgo S190426c: INT Observations of ZTF19aassfws
  11. LIGO/Virgo S190426c: Discovery Channel Telescope Follow-Up of ZTF19aassfws
  12. LIGO/Virgo S190426c (BHNS candidate): Implications from Numerical Relativity
  13. LIGO/Virgo S190426c: Konus-Wind observations
  14. LIGO/Virgo S190503bf: AstroSat CZTI upper limits
  15. LIGO/Virgo S190426c: Update on Source Classification
  16. LIGO/Virgo S190426c: Gaia19boq 0.6m BOOTES-5/JGT, 1.5m OSN and 10.4m GTC observations
  17. LIGO/Virgo S190426c: ZTF19aaslzjf, ZTF19aasmftm and ZTF19aasmddt 1.5m OSN and 10.4m GTC observations
  18. LIGO/Virgo S190426c: ZTF pre-detections of Gaia19bpm AT2019ehs
  19. LIGO/Virgo S190426c: Gaia Photometric Alerts transient candidate
  20. LIGO/Virgo S190426c: Swift rapid follow-up observations of S190425z and S190426c and URL for observation log for all future events
  21. LIGO/Virgo S190426c: GROWTH India follow-up of GRAWITA transient
  22. LIGO/Virgo S190426c: PS1 historical detections and ZTF photometry of Gaia19boq AT2019egk
  23. LIGO/Virgo S190426c: YAHPT Optical Observation
  24. LIGO/Virgo S190426c: Gaia Photometric Alerts transient candidate
  25. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  26. LIGO/Virgo S190426c: MASTER analysys of GRAWITA transients
  27. LIGO/Virgo S190426c: GRAWITA transients from Asiago Schmidt wide field observations
  28. LIGO/Virgo S190426c: Continued LOAO Observation
  29. LIGO/Virgo S190426c: Additional Candidates from the Zwicky Transient Facility
  30. LIGO/Virgo S190426c: Continued infrared wide-field search with Palomar Gattini-IR
  31. LIGO/Virgo S190426c: OAJ-GRANDMA observation report
  32. LIGO/Virgo S190426c: ASAS-SN observations
  33. LIGO/Virgo S190426c: LOAO Observation
  34. LIGO/Virgo S190426c: DG19ytre and DG19kplb 1.5m OSN imaging and 10.4m GTC spectroscopy
  35. LIGO/Virgo S190426c: GROWTH India follow-up
  36. LIGO/Virgo S190426c: DDOTI/OAN Optical Observations
  37. LIGO/Virgo S190426c: RATIR Optical and NIR Observations of Galaxies
  38. LIGO/Virgo S190426c: J-GEM optical/NIR follow-up observations
  39. LIGO/Virgo S190426c: COATLI Optical Observations of Galaxies
  40. LIGO/Virgo S190426c: MMT Follow-Up Observations
  41. LIGO/Virgo S190426c: GOTO optical coverage - no notable counterparts
  42. LIGO/Virgo S190426c: Lick/KAIT Follow-Up Observations
  43. LIGO/Virgo S190426c: CNEOST Optical Observations
  44. LIGO/Virgo S190426c: Infrared Wide-field Search with Palomar Gattini-IR
  45. LIGO/Virgo S190426c: Optical Wide-field Search with the Zwicky Transient Facility
  46. LIGO/Virgo S190426c: Nanshan/NEXT Observation of Galaxies
  47. LIGO/Virgo S190426c: Insight-HXMT/HE observation
  48. LIGO/Virgo S190426c: Updated localization to fix data format issue
  49. LIGO/Virgo S190426c: Hobby-Eberly Telescope VIRUS observations of target galaxies.
  50. LIGO/Virgo S190426c: Updated localization from LIGO and Virgo data
  51. LIGO/Virgo S190426c: CALET Observations
  52. LIGO/Virgo S190426c: Imaging confirmation and host spectroscopy of DG19vkgf
  53. LIGO/Virgo S190426c: Swift-XRT sources
  54. ANTARES follow-up of the GW candidate S190426c
  55. LIGO/Virgo S190426c: Red and blue transients identified with DECam
  56. LIGO/Virgo S190426c: MAXI/GSC Observations
  57. LIGO/Virgo S190426c: GROWTH India follow-up
  58. LIGO/Virgo S190426c: Public DECam Observations
  59. LIGO/Virgo S190426c: Swift/BAT Counterpart Search
  60. LIGO/Virgo S190426c: STARE2 simultaneous L-band radio observations
  61. LIGO/Virgo S190426c: Nemo is Unrelated
  62. LIGO/Virgo S190426c: a possible lensed NS-NS merger
  63. LIGO/Virgo S190426c: Tentative Red Transient Candidate from Las Cumbres Observatory
  64. LIGO/Virgo S190426c: Fermi GBM Observations
  65. LIGO/Virgo S190426c: SAO optical observation
  66. LIGO/Virgo S190426c: AGILE-GRID Observations
  67. LIGO-Virgo S190426c: AGILE MCAL observation
  68. LIGO/Virgo S190426c: Potential host galaxies from the GLADE catalog
  69. LIGO/Virgo S190426c: INTEGRAL prompt observation
  70. LIGO/Virgo S190426c: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo S190426c Global MASTER-Net observations report
  72. LIGO/Virgo S190426c: HAWC follow-up
  73. LIGO/Virgo S190426c: IceCube Neutrino Search

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