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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').
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To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

73 results found.

  1. LIGO/Virgo G277583: INTEGRAL was inactive at the time of the event
  2. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  3. LIGO/Virgo G211117 / GW151226: Sky maps and other data available in LOSC
  4. LIGO/Virgo G211117/GW151226: serendipitous XMM-Newton slew observations
  5. LIGO/Virgo G211117: Astrosat CZTI upper limits
  6. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  7. LIGO Virgo G211117: Additional MWA Observations
  8. LIGO/Virgo G211117: 10.4m GTC follow-up of PS15dpn
  9. LIGO/Virgo G211117: LOFAR follow-up
  10. LIGO/Virgo G211117: CALET GBM Observations
  11. LIGO/Virgo G211117: EWE for NOWT follow-up of northern sky
  12. LIGO/Virgo G211117: HAWC follow-up of northern sky
  13. LIGO/Virgo G211117: GRAWITA LBT follow-up of PS15dpn
  14. LIGO/Virgo G211117: LOFAR follow-up
  15. LIGO Virgo G211117: MWA Observations
  16. LIGO/Virgo G211117: Refined localization from CBC parameter estimation
  17. LIGO/Virgo G211117: Preliminary VLA observation summary of PS15dpn
  18. LIGO/Virgo G211117: Further Swift-XRT sources
  19. LIGO/Virgo G211117: INAF NOT follow-up of PanStarrs candidates
  20. LIGO/Virgo G211117: Updated FAR estimate based on offline re-analysis
  21. LIGO/Virgo G211117: Distance estimate from GW data compared to redshift of PS15dpn
  22. LIGO/Virgo G211117: Swift observations of PS15dpn
  23. LIGO/Virgo G211117: iPTF Observations of PS15dpn
  24. LIGO/Virgo G211117: PESSTO classification of MASTER J165420.77-615258
  25. LIGO/Virgo G211117: VLA follow-up
  26. LIGO/Virgo G211117: Pi of the Sky observations
  27. LIGO/Virgo G211117: VISTA imaging
  28. LIGO/Virgo G211117: Subaru Hyper Suprime-Cam follow-up observation
  29. LIGO/Virgo G211117: MASTER OT in ESO138-006 galaxy
  30. LIGO/Virgo G211117: Further Swift-XRT sources
  31. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  32. LIGO/Virgo G211117: Summary of Pan-STARRS transients
  33. LIGO/Virgo G211117: INAF TNG follow-up of Kanata telescope candidate
  34. LIGO/Virgo G211117: Fermi/LAT observations
  35. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  36. LIGO/Virgo G211117: Gemini classification of 7 Pan-STARRS transients
  37. LIGO/Virgo G211117: LOFAR follow-up
  38. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  39. LIGO/Virgo G211117: PESSTO classification of Pan-STARRS transients
  40. LIGO/Virgo G211117: MASTER OTs 26.XII.2015 - 01.I.2016
  41. LIGO/Virgo G211117: CSS/CRTS observations on 29/30 Dec 2015 UT
  42. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28 - 30
  43. LIGO/Virgo G211117: Liverpool Telescope classification of EM candidates
  44. LIGO/Virgo G211117: FLOYDS Classification of SMTJ13331687-1607330 as a Two-Week-Old Type Ia Supernova
  45. LIGO/Virgo G211117: LBT follow-up imaging of iPTF15fhq
  46. LIGO/Virgo G211117: 44 transients from Pan-STARRS data during 2015-12-28/30
  47. LIGO/Virgo G211117: MAXI/GSC observations
  48. LIGO/Virgo G211117: Liverpool Telescope followup of EM candidates
  49. LIGO/Virgo G211117: VLA follow-up
  50. LIGO/Virgo G211117: LBT Follow-up of iPTF15fen
  51. LIGO/Virgo G211117: MAGIC very-high energy gamma-ray observations
  52. LIGO/Virgo G211117: INAF TNG follow-up of MASTER OT J020906.21+013800.1
  53. LIGO/Virgo G211117: OAO-WFC NIR follow-up observations
  54. LIGO/Virgo G211117: SkyMapper observations and transient candidate
  55. LIGO/Virgo G211117: MASTER Observations of the 3 iPTF candidates
  56. LIGO/Virgo G211117: Optical Observations with Kiso Schmidt telescope and KWFC
  57. LIGO/Virgo G211117: List of near-term future observation regions by Project Mini-GWAC of SVOM
  58. LIGO/Virgo G211117: iPTF Optical Transient Candidates
  59. LIGO/Virgo G211117: La Silla - QUEST observations 2015 Dec 28, 29
  60. LIGO/Virgo G211117: Further Swift-XRT sources
  61. LIGO/Virgo G211117: DESGW program observations with DECam
  62. LIGO/Virgo G211117: Optical NIR observation with Kanata telescope
  63. LIGO/Virgo G211117: Fermi GBM Observations
  64. LIGO/Virgo G211117: Optical follow-up with Kanata telescope
  65. LIGO/Virgo G211117: MASTER Observations and Inspection + OT
  66. LIGO/Virgo G211117: INTEGRAL was inactive at the time of the event
  67. LIGO/Virgo G211117: Pan-STARRS1 observations 2015-12-28
  68. LIGO/Virgo G211117: INAF VST-ESO PARANAL observations
  69. LIGO/Virgo G211117: Further Swift-XRT sources
  70. LIGO/Virgo G211117: Swift-XRT sources
  71. LIGO/Virgo G211117: SWASP optical observations
  72. LIGO/Virgo G211117: MASTER possible OT detection at the begining of inspection
  73. LIGO/Virgo G211117: Identification of a GW CBC Candidate

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