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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"

5822 results found.

  1. LIGO/Virgo G299232: LOFAR follow-up
  2. GRB 171003A: Swift detection of a burst or a Galactic Transient
  3. LIGO/Virgo G298048: Record of all e-MERLIN results to date on SSS17a
  4. LIGO/Virgo G299232/GW170825: serendipitous XMM-Newton slew observations
  5. LIGO/Virgo G298936/GW170823: serendipitous XMM-Newton slew observations
  6. GRB 170728B: Kottamia R-band observation
  7. IceCube-170922A: Swift-XRT observations
  8. LIGO/Virgo G298048: MWA Observations of Error Region
  9. IceCube-170922A: HAWC follow-up
  10. GRB 170906A: Insight-HXMT detection
  11. GRB 170921C: Insight-HXMT detection
  12. INTEGRAL SPI-ACS observation of AMON IceCube-170922A
  13. GRB 170921A: RATIR Optical Afterglow Detection and NIR Observations
  14. LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
  15. GRB 170918A: Insight-HXMT detection
  16. GRB 170921A: Nanshan optical upper limit
  17. GRB 170921A: MITSuME Okayama upper limits
  18. LIGO/Virgo G298048: SSS17a photometry of CHILESCOPE observatory
  19. LIGO/Virgo G298048: Milliarcsecond imaging of the NGC 4993 central radio source
  20. Fermi-GBM GRB misclassifications
  21. GRB 170912C: Insight-HXMT detection
  22. LIGO/VIRGO G298048: MeerKAT observations of SSS17a
  23. LIGO/Virgo G297595: NIR Observations following GW170814
  24. LIGO/Virgo G298048: Danish Telescope Observations of SSS17a/DLT17ck
  25. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  26. GRB 170912A: Prompt enhanced Swift-XRT position
  27. Konus-Wind observation of GRB 170904A
  28. LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
  29. GRB 170906C: COATLI Observations
  30. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  31. IPN Triangulation of GRB 170904A (long/very bright)
  32. GRB 170901B: Insight-HXMT detection
  33. GRB 170904A: Insight-HXMT detection
  34. LIGO/VIRGO G298048: Precise position of SSS17a based on HST and Gaia
  35. LIGO/Virgo G299232: LOFAR follow-up
  36. GRB 170903A: UAFO /ISON optical upper limit
  37. GRB 170903A: MITSuME Okayama upper limits
  38. GRB 170903A: Nanshan optical upper limit
  39. Swift Triggers on MAXI J1535-571
  40. LIGO/Virgo G297595: DECam observations of BBH merger region of interest
  41. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  42. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  43. LIGO/Virgo G299232: GRAWITA Asiago optical observations
  44. LIGO/Virgo G298936: PIRATE observations
  45. LIGO/Virgo G298048: GMRT Follow-up of SSS17a at 1.4 GHz
  46. LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
  47. LIGO/Virgo G299232: PIRATE observations of MASTER OT J033744.97+723159.0
  48. LIGO/Virgo G298048: ALMA upper limits on 98 GHz emission from SSS17a
  49. LIGO/Virgo G298048: Further ATCA follow-up of SSS17a in NGC 4993
  50. LIGO/Virgo G299232 TZAC/TAROT observations
  51. LIGO/Virgo G299232/PGWB170825.55: MASTER Global-Net OT inside NGC1343 discovery
  52. GRB 170827A: Swift detection of a burst
  53. LIGO/VIRGO G298048: INAF VST-ESO PARANAL observations of NGC4993
  54. GRB 170822A: AstroSat CZTI detection
  55. LIGO/Virgo G298048: MASTER Global-Net early optical observations and the Possible KiloNova SSS17a in NGC 4993 photometry and merging rate
  56. LIGO/Virgo G298048: HAWC follow-up
  57. LIGO/Virgo G298048: LWA radio observations
  58. Konus-Wind observation of GRB 170822A
  59. LIGO/Virgo G298048: INTEGRAL pointed follow-up observations
  60. LIGO/Virgo G298048: ATCA follow-up of SSS17a in NGC 4993
  61. LIGO/Virgo G298048: Chandra X-ray observations
  62. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  63. GRB 170822A:BOOTES-5/JGT optical afterglow candidate
  64. GRB 170822A: Swift detection of a burst
  65. LIGO/Virgo G298048: MWA Observations of Error Region
  66. LIGO/Virgo G298048: VLA observation at 15 GHz
  67. LIGO/Virgo G298048: observations of optical counterpart candidate with CHILESCOPE observatory
  68. LIGO/Virgo G298048: ATCA 8.5 GHz observations of galaxies in the localisation volume
  69. LIGO/Virgo G298048: NuSTAR limits on X-ray emission
  70. LIGO/Virgo G298048: ASKAP follow up
  71. LIGO/Virgo G298048: TOROS optical counterpart search
  72. LIGO/Virgo G298048: VLA observation at 6 GHz
  73. LIGO/Virgo G298048: GROND observations of candidate optical counterpart
  74. LIGO/Virgo G298048: VLT linear polarimetry
  75. LIGO/Virgo G298048: Further VLA Observations
  76. LIGO/Virgo G298048: HSC observations of the OT candidate of G298048
  77. LIGO/Virgo G298048: GROND photometry of candidate optical counterpart reveals brightening in the NIR
  78. LIGO/Virgo G298048: Rapid Evolution of Possible Counterpart
  79. LIGO/Virgo G298048: ATCA upper limits on radio emission from optical source SSS17a in NGC 4993
  80. LIGO/Virgo G298048: Brightening of Possible Counterpart
  81. LIGO/Virgo G298048: AGILE-GRID analysis of the potential counterpart field
  82. LIGO/Virgo G298048: Observation of the potential optical counterpart in NGC 4993
  83. LIGO/Virgo G298048: Subaru HSC z-band photometry of the possible optical counterpart
  84. LIGO/Virgo G298048: SkyMapper uvgri photometry of the candidate in NGC 4933
  85. LIGO/Virgo G298048: ATCA detection of a radio source coincident with NGC 4993
  86. LIGO/Virgo G298048: TZAC TAROT Reunion (TRE) observations
  87. LIGO/Virgo G298048: REM optical/NIR observations
  88. LIGO/Virgo G298048: Pan-STARRS detections and izy photometry of the possible optical/NIR counterpart in NGC4993
  89. LIGO/Virgo G298048: Magellan g-band Imaging of the Potential Optical Counterpart Associated with NGC 4993
  90. LIGO/Virgo G298048: Subaru HSC follow-up observations
  91. LIGO/VIRGO G298048: Magellan Optical Spectrum of the Potential Optical Counterpart Associated with NGC 4993
  92. LIGO/Virgo G298048: VLA Detection
  93. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival SkyMapper Transient Survey Data
  94. LIGO/Virgo G298048: Optical Candidate Shows No Evidence for Previous Activity in Archival ASAS-SN Data
  95. LIGO/Virgo G298048: DLT40 optical candidate
  96. LIGO/Virgo G298048: Potential optical counterpart discovered by Swope telescope
  97. LIGO/Virgo G297595: MASTER MASTER Bright PSN detection in error-box
  98. LIGO/Virgo G297595: INAF VST-ESO PARANAL observations
  99. LIGO/Virgo G297595: Subaru Hyper Suprime-Cam follow-up observations
  100. LIGO/Virgo G296853: Pierre Auger Observatory neutrino follow-up

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