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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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').
Advanced Search

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.

Advanced Search Examples (click to copy):

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

16316 results found.

  1. GRB 171027A: LCO 1-m telescope observations
  2. GRB 171027A: MASTER-OAFA (Argentina) early prompt optical observations
  3. Swift Trigger 781740 is not a burst
  4. GRB 171020A: Continued RATIR Optical and NIR Observation
  5. GRB 171020A: TAROT Calern observatory optical observations
  6. GRB 171020A: Swift/UVOT Upper Limits
  7. GRB 171020A: NOT spectroscopic redshift
  8. GRB 171020A: RATIR Optical and NIR Observations
  9. GRB 171020A: LT observations
  10. GRB 171020A: Mini-MegaTORTORA upper limits on simultaneous optical emission
  11. GRB 171020A: NOT optical afterglow detection
  12. GRB 171010A: VLA Detection
  13. GRB 171010A : Optical observations from HCT
  14. GRB 171010A: RATIR Optical and NIR Observations
  15. BAT trigger 778435 is not a GRB.
  16. GRB 171013A: TAROT Calern observatory optical observations
  17. GRB 171010A: ePESSTO NTT spectroscopic redshift
  18. GRB 171010A: MITSuME Akeno Optical Observation
  19. GRB 171010A: NOT optical observations
  20. GRB 171011A: TAROT Calern observatory optical observations
  21. GRB 171011A: MASTER-SAAO optical observations
  22. GRB 171010A: LCO 1m telescope observations
  23. GRB 171010A: optical observations
  24. GRB 171007A: Swift/UVOT Upper Limits
  25. GRB 171007A: RATIR Optical and NIR Observations
  26. GRB 171004A: Swift/UVOT Upper Limits
  27. LIGO/Virgo G299232: SWASP optical imaging coverage
  28. GRB 171004A: RATIR Optical and NIR Observations
  29. GRB 170710A: LCO Observations
  30. LIGO/Virgo G299232: MAGIC Cherenkov Telescopes observations
  31. LIGO/Virgo G299232: LOFAR follow-up
  32. GRB 171003A: LT early optical observations
  33. GRB 171001A: RATIR Optical and NIR Observations
  34. GRB 171001A: Nanshan-0.36m optical afterglow detections
  35. GRB171001A: D50 optical limit
  36. LIGO/VIRGO G299232: AMI-LA Observations of the optical transient Swift J014008.5+343403.6
  37. 3.6m Devasthal Optical Telescope observations of GRB 170428A
  38. LIGO/VIRGO G298048: VLA detection of the radio counterpart at 6 GHz
  39. GRB 170728B: Kottamia R-band observation
  40. LIGO/Virgo G298048: Summary of Pi of the Sky observations
  41. LIGO/VIRGO G298048: Latest 3 GHz Detection of Radio Counterpart to SSS17a
  42. GRB 170921A: RATIR Optical Afterglow Detection and NIR Observations
  43. LIGO/Virgo G298048: SRT observations of SSS17a in NGC 4993
  44. GRB 170921A: Swift/UVOT Upper Limits
  45. GRB 170921A: LCO 2m telescope observations
  46. GRB 170921A: NOT optical observations
  47. LIGO/Virgo G298048: LCO FLOYDS and Gemini Spectroscopy
  48. GRB 170921A: Nanshan optical upper limit
  49. GRB 170921A: MITSuME Okayama upper limits
  50. GRB 170921A: TAROT Calern observatory optical observations
  51. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  52. LIGO/Virgo G298048: Desert Fireball Network simultaneous optical observations of the SSS17a/DLT17ck.
  53. LIGO/Virgo G298048: Danish Telescope Observations of SSS17a/DLT17ck
  54. LIGO/Virgo G298048: ATLAS pre-discovery limits 601 to 16 days before first detection of SSS17a/DLT17ck
  55. LIGO/Virgo G298048: AST3-2 observations of SSS17a/DLT17ck from Antarctica
  56. GRB 170912B: Swift/UVOT Upper Limits
  57. GRB 170912A: Swift/UVOT Upper-Limits
  58. LIGO/Virgo G297595: Las Cumbres Observatory Optical Follow-Up
  59. LIGO/Virgo G298048: VLA radio non-detection
  60. LIGO/Virgo G298048: VLBA upper limits at 8.7GHz for the GW counterpart SSS17a/DLT17ck on August 20-21 UT
  61. GRB 170906B: Swift/UVOT Upper Limits
  62. GRB 170906C: optical observations
  63. LIGO/Virgo G298048: ATCA observations of of SSS17a in NGC 4993
  64. GRB 170906C: Swift/UVOT Upper Limits
  65. LIGO/Virgo G298048 GRAWITA: VST-ESO PARANAL follow up of SSS17a in NGC4993.
  66. GRB 170906A: MASTER-OAFA (Argentina) early automatic OT detection
  67. GRB 170906A: REM optical/NIR observations
  68. GRB 170906A: Swift detection of a burst with an optical afterglow
  69. LIGO/VIRGO G298048: Radio detection of SSS17a at 6 GHz with the VLA
  70. LIGO/VIRGO G298048: Radio detection of SSS17a at 3GHz with the VLA/JAGWAR
  71. LIGO/Virgo G299232: Maidanak observations of optical transient SwiftJ014008.5+343403.6
  72. LIGO/Virgo G299232: LOFAR follow-up
  73. Swift Trigger on continued activity of MAXI J1535-571
  74. GRB 170827A: LCO Observations
  75. GRB 170903A: Swift/UVOT Upper Limits
  76. GRB 170903A: UAFO /ISON optical upper limit
  77. LIGO/Virgo G298048: e-MERLIN upper limits on 5 GHz compact emission from SSS17a
  78. LIGO/Virgo G298048: ATCA monitoring of SSS17a in NGC 4993
  79. LIGO/Virgo G299232: RoboPol observations of MASTER OT J033744.97+723159.0
  80. GRB 170903A: MITSuME Okayama upper limits
  81. LIGO/Virgo G298048: Chandra X-ray Update on GW170817
  82. GRB 170903A: Nanshan optical upper limit
  83. LIGO/Virgo G298048: Chandra monitoring of the X-ray emission from SSS17a
  84. LIGO/Virgo G298048: Continued X-ray monitoring and X-ray detection of GW170817 [erratum]]
  85. LIGO/Virgo G298048: AGILE-GRID analysis of data contemporary to X-ray emission from SSS17a in NGC4993
  86. LIGO/Virgo G298048
  87. LIGO/Virgo G298048: Hubble Space Telescope observations
  88. LIGO/Virgo G299232: XSNAOC spectral observation of MASTER OTJ033744.97+723159.0
  89. LIGO/Virgo G298048: Possible Plateau in Ks band revealed by continued Gemini-South observations
  90. LIGO/Virgo G298048: Continued Gemini South observations
  91. LIGO/Virgo G299232: GRAWITA Asiago optical observations
  92. LIGO/Virgo G299232: continued WHT observations of the field of SwiftJ014008.5+343403.6
  93. LIGO/Virgo G298048: GMRT Follow-up of SSS17a at 1.4 GHz
  94. LIGO/Virgo G299232: GRAWITA Campo Imperatore optical observations
  95. LIGO/Virgo G298048: Discovery of X-ray emission from SSS17a in NGC4993
  96. GRB 170830A: iTelescope optical observations
  97. LIGO/Virgo G299232: SVOM/2.16-m Optical Telescope Observations of Swift UVOT Transient
  98. LIGO/Virgo G299232: Further Swift/UVOT Observations of Optical Transient SwiftJ014008.5+343403.6
  99. LIGO/Virgo G299232 : RATIR Optical and NIR Observations of Swift UVOT source
  100. LIGO/Virgo G299232: WHT non-detection u-band optical transient

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