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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"

4738 results found.

  1. LIGO/Virgo G268556: VLA follow-up of iPTF17cw
  2. GRB 170111A: MASTER-OAFA (Argentina) prompt OT observations
  3. GRB 170109A: POLAR Observation
  4. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  5. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  6. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  7. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  8. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  9. GRB 161229A: POLAR observation
  10. GRB 161214A: MASTER-IAC early optical observations
  11. Fermi GBM trigger 503982114/161221126 is not a GRB
  12. GRB 161217B: POLAR Observation
  13. IPN Triangulation of GRB 161218B (long/very bright)
  14. GRB 161218A: CALET Gamma-Ray Burst Monitor detection
  15. Konus-Wind observation of GRB 161218A
  16. GRB 161218A: Swift detection of a burst
  17. GRB 161202A: MITSuME Okayama upper limits
  18. GRB 161123A: MAXI/GSC detection
  19. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  20. GRB 161108A: NOT candidate afterglow
  21. GRB 161108A: Swift detection of a burst
  22. Fermi LAT Gamma-ray Observations of IceCube-161103
  23. IceCube-161103: Konus-Wind upper limits
  24. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161103
  25. IceCube-161103: MASTER follow-up observations
  26. HAWC follow up of IceCube-161103
  27. IceCube-161103: IceCube observation of a very-high-energy neutrino
  28. Swift Trigger 718766 is not an astrophysical event.
  29. GRB 161017A: LT optical observations
  30. GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
  31. GRB161017A: optical observations with 1-m LCOGT McDonald
  32. GRB 161017A: TNG optical observations
  33. GRB 161017A: MITSuME Akeno Optical Observation
  34. GRB161017.74 MASTER-Net OT detection
  35. Konus-Wind observation of GRB 161015A
  36. GRB161015A: AstroSat CZTI detection
  37. GRB 161015A: Fermi GBM detection
  38. GRB 161015A: Fermi-LAT detection
  39. GRB 161014A: TNG optical observations
  40. GRB 161014A: Continued MITSuME Akeno Optical Observation
  41. GRB 161014A : Xinglong TNT optical observation
  42. GRB 160925A: Kottamia R-band observation
  43. GRB 161001A: GROND afterglow candidate
  44. GRB 160814A: MAXI/GSC detection
  45. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  46. GRB 160804A: ISON/UAFO optical observations
  47. Swift follow up of IceCube-160731A
  48. Swift Trigger 704327: MASTER syncronous optical observations
  49. Swift Trigger 704327: a possible GRB
  50. GRB 160712A: GROND observations
  51. GRB 160629A: AbAO optical observations
  52. GRB 160703A: MITSuME Ishigakijima Optical Observation
  53. GRB 160703A: MITSuME Akeno Optical Observations
  54. GRB 160625B: RTT150 optical observations
  55. GRB 160625B: MITSuME Ishigakijima Optical Observation
  56. Trigger 701590: Swift detection of a bright outburst from SGR 1935+2154
  57. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  58. GRB 160622A: Swift detection of a possible short GRB or a new SGR
  59. LIGO/Virgo G211117/GW151226: serendipitous XMM-Newton slew observations
  60. SWIFT J174540.2-290037, Swift-BAT refined analysis (trigger 689956)
  61. Trigger 689956: Swift detection of a source near the Galactic center
  62. Trigger 689353 (possible transient near Sgr A*), Swift-BAT refined analysis
  63. Konus-Wind observation of GRB 160530A
  64. IPN Triangulation of GRB 160530A
  65. GRB 160525B: MITSuME Akeno optical upper limits
  66. GRB 160530A: discovery with the Compton Spectrometer and Imager
  67. The nature of the Fermi/GBM trigger 160523919 is unknown.
  68. Swift detection of SGR 1935+2154
  69. GRB 160521A: a long GRB detected by INTEGRAL
  70. GRB 160509A: MAXI/GSC refined analysis
  71. LIGO/Virgo G211117: Astrosat CZTI upper limits
  72. GRB 160506A: Swift detection of a burst
  73. ICECUBE-160427A : Pan-STARRS imaging and optical transients in the field
  74. GRB 160503A: Fermi GBM observation
  75. GRB 160503A: Fermi-LAT detection
  76. GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
  77. GRB 160417A: GMG observations
  78. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  79. GRB 160409A found in Swift BAT ground analysis
  80. GRB 160410A: Swift/UVOT Detection
  81. GRB 160410A: Swift detection of a (possibly-short) burst with an optical counterpart
  82. LIGO/Virgo G211117: LOFAR follow-up
  83. GRB 160327A: JCMT SCUBA-2 sub-mm observation
  84. GRB 160327A: Continued RATIR Optical and NIR Observations
  85. GRB 160327A: Mondy optical upper limit
  86. GRB 160327A: RATIR Optical and NIR Afterglow Detection
  87. GRB 160325A: GROND Upper Limits
  88. GRB 160325A: Swift detection of a burst
  89. Swift detects GX 301-2 in very high state
  90. GRB 160321A: AbAO optical observations
  91. GRB 160321A: Possible RATIR Optical and NIR Detections
  92. GRB 160321A: MASTER observations zero Galaxy latitude GRB
  93. GRB 160310A: Terskol 2-m observations
  94. GRB 160310A: A further Swift-XRT observation, no afterglow detected
  95. GRB 160314A: Continued RATIR Optical and NIR Observations
  96. GRB 160313A: Mondy optical upper limit
  97. GRB 160314A: GROND optical/NIR observations
  98. GRB 160314A: ISON-Ussuriysk optical upper limit, updated photometry and correction of GCN 19184
  99. GRB 160314A: RATIR Optical and NIR Observations
  100. GRB 160314A: Mondy optical observations

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