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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.

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

5556 results found.

  1. GRB 170205A: Enhanced Swift-XRT position
  2. Fermi GBM trigger 507959893/170205165 is not a GRB
  3. GRB 170202A: SMARTS optical/IR afterglow observations
  4. GRB 170205A: Swift detection of a burst with an optical counterpart
  5. GRB 170202A: SQUEAN Observation
  6. GRB 170202A: LCO FTN observations
  7. GRB 170202A VLT/X-shooter redshift [minor correction]
  8. GRB 170203A: Swift detection of a burst
  9. LIGO/Virgo G270580: Las Cumbres Observatory Follow-up Observations
  10. LIGO/Virgo G270580: Liverpool Telescope classification of EM candidates
  11. LIGO/Virgo G270580: Pan-STARRS coverage and 124 optical transients
  12. LIGO/Virgo G270580: Pan-STARRS coverage and bright, rising transient PS17yt
  13. LIGO/Virgo G270580: Swift-XRT sources
  14. LIGO/Virgo G268556: Global MASTER Net 21 OTs detection
  15. Swift Trigger #733426: possible detection of a burst or transient
  16. GRB 170113A: Swift/UVOT Observations
  17. GRB 170112A: Swift detection of a short burst
  18. LIGO/Virgo G268556: Additional GROWTH follow up observation of iPTF Optical Transient Candidates
  19. LIGO/Virgo G268556: VLA follow-up of iPTF17cw
  20. GRB 170111A: MASTER-OAFA (Argentina) prompt OT observations
  21. GRB 170109A: POLAR Observation
  22. LIGO/Virgo G268556: GWAC_F60B (60cm) follow-up two events of EWE001 and EWE002
  23. LIGO/Virgo G268556: iPTF Optical Transient Candidates
  24. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  25. LIGO/Virgo G211117 / GW151226: LOFAR follow-up
  26. LIGO/Virgo G268556: observation regions by Project Mini-GWAC of SVOM
  27. GRB 161229A: POLAR observation
  28. GRB 161214A: MASTER-IAC early optical observations
  29. Fermi GBM trigger 503982114/161221126 is not a GRB
  30. GRB 161217B: POLAR Observation
  31. IPN Triangulation of GRB 161218B (long/very bright)
  32. GRB 161218A: CALET Gamma-Ray Burst Monitor detection
  33. Konus-Wind observation of GRB 161218A
  34. GRB 161218A: Swift detection of a burst
  35. GRB 161202A: MITSuME Okayama upper limits
  36. GRB 161123A: MAXI/GSC detection
  37. GRB 161119A: MASTER-SAAO possible OT detection during Fermi Alert
  38. GRB 161108A: NOT candidate afterglow
  39. GRB 161108A: Swift detection of a burst
  40. Fermi LAT Gamma-ray Observations of IceCube-161103
  41. IceCube-161103: Konus-Wind upper limits
  42. INTEGRAL SPI-ACS and IBIS/Veto observation of IceCube-161103
  43. IceCube-161103: MASTER follow-up observations
  44. HAWC follow up of IceCube-161103
  45. IceCube-161103: IceCube observation of a very-high-energy neutrino
  46. Swift Trigger 718766 is not an astrophysical event.
  47. GRB 161017A: LT optical observations
  48. GRB 161017A: Lomonosov Gamma Ray and MASTER Optical prompt observations
  49. GRB161017A: optical observations with 1-m LCOGT McDonald
  50. GRB 161017A: TNG optical observations
  51. GRB 161017A: MITSuME Akeno Optical Observation
  52. GRB161017.74 MASTER-Net OT detection
  53. Konus-Wind observation of GRB 161015A
  54. GRB161015A: AstroSat CZTI detection
  55. GRB 161015A: Fermi GBM detection
  56. GRB 161015A: Fermi-LAT detection
  57. GRB 161014A: TNG optical observations
  58. GRB 161014A: Continued MITSuME Akeno Optical Observation
  59. GRB 161014A : Xinglong TNT optical observation
  60. GRB 160925A: Kottamia R-band observation
  61. GRB 161001A: GROND afterglow candidate
  62. GRB 160814A: MAXI/GSC detection
  63. Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
  64. GRB 160804A: ISON/UAFO optical observations
  65. Swift follow up of IceCube-160731A
  66. Swift Trigger 704327: MASTER syncronous optical observations
  67. Swift Trigger 704327: a possible GRB
  68. GRB 160712A: GROND observations
  69. GRB 160629A: AbAO optical observations
  70. GRB 160703A: MITSuME Ishigakijima Optical Observation
  71. GRB 160703A: MITSuME Akeno Optical Observations
  72. GRB 160625B: RTT150 optical observations
  73. GRB 160625B: MITSuME Ishigakijima Optical Observation
  74. Trigger 701590: Swift detection of a bright outburst from SGR 1935+2154
  75. Swift-BAT refined analysis of the recent outburst from SGR 1617-5103 (a.k.a. 1E 161348-5055 and 2E 1613.5-5053)
  76. GRB 160622A: Swift detection of a possible short GRB or a new SGR
  77. LIGO/Virgo G211117/GW151226: serendipitous XMM-Newton slew observations
  78. SWIFT J174540.2-290037, Swift-BAT refined analysis (trigger 689956)
  79. Trigger 689956: Swift detection of a source near the Galactic center
  80. Trigger 689353 (possible transient near Sgr A*), Swift-BAT refined analysis
  81. Konus-Wind observation of GRB 160530A
  82. IPN Triangulation of GRB 160530A
  83. GRB 160525B: MITSuME Akeno optical upper limits
  84. GRB 160530A: discovery with the Compton Spectrometer and Imager
  85. The nature of the Fermi/GBM trigger 160523919 is unknown.
  86. Swift detection of SGR 1935+2154
  87. GRB 160521A: a long GRB detected by INTEGRAL
  88. GRB 160509A: MAXI/GSC refined analysis
  89. LIGO/Virgo G211117: Astrosat CZTI upper limits
  90. GRB 160506A: Swift detection of a burst
  91. ICECUBE-160427A : Pan-STARRS imaging and optical transients in the field
  92. GRB 160503A: Fermi GBM observation
  93. GRB 160503A: Fermi-LAT detection
  94. GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
  95. GRB 160417A: GMG observations
  96. LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
  97. GRB 160409A found in Swift BAT ground analysis
  98. GRB 160410A: Swift/UVOT Detection
  99. GRB 160410A: Swift detection of a (possibly-short) burst with an optical counterpart
  100. LIGO/Virgo G211117: LOFAR follow-up

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