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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"

21089 results found.

  1. GRB 090515: VLA observations
  2. GRB 090515: ROVOR Upper Limit
  3. GRB 090515: MMT/MMIRS NIR Upper Limit
  4. GRB 090515: Swift/UVOT Observations
  5. GRB 090509 - Zadko Telescope observations
  6. GRB 090515: Gemini-N upper limit
  7. GRB 090515: WIYN NIR Upper Limit
  8. GRB 090515: Super-LOTIS Upper Limits
  9. GRB 090515: PAIRITEL Upper Limits
  10. GRB 090510, Radio limits
  11. GRB090510: VLT/FORS2 spectroscopic redshift
  12. GRB 090510: GROND observations
  13. GRB 090510: Swift/UVOT host galaxy candidates
  14. GRB 090510: UVOT refined analysis
  15. GRB 090510: NOT afterglow confirmation
  16. GRB 090509, SMARTS optical/IR afterglow observations
  17. GRB 090418A: optical observation
  18. GRB 090509: REM NIR afterglow
  19. GRB 090323: optical observations
  20. GRB 090423: 250 GHz upper limit for a z=8.2 GRB with MAMBO-2 at the IRAM 30m
  21. GRB 080913: 250 GHz upper limit for a z=6.7 GRB with MAMBO-2 at the IRAM 30m
  22. GRB 090424: optical observations
  23. GRB 090427: GROND observations
  24. GRB 090429A: ROVOR magnitude limit
  25. Refined analysis of ICSP VLF observation of SGR J1550-5418 bursts on 22nd January, 2009
  26. GRB 090426: optical observations
  27. GRB 090429B: Gemini-N further nIR observations
  28. GRB 090424: YNAO-GMG observations
  29. GRB 090429A: GROND upper limits
  30. GRB 090418A BVRcIc field calibration
  31. GRB090429B: Gemini-N infrared IR candidate
  32. GRB 090426: YNAO-GMG observations
  33. GRB 090429B: VLT upper limits
  34. GRB 090429B: GROND Observations
  35. GRB 090429B: Super-LOTIS early observations
  36. GRB 090423: pseudo burst at z=1 and its relation to GRB 080913
  37. GRB 090424: Continued R-band monitoring
  38. GRB 090423: CARMA mm observations
  39. GRB 090423: millimeter detection
  40. GRB 090426: VLT spectroscopy
  41. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  42. GRB090426 Swift/UVOT observations
  43. GRB 090423: GROND second epoch imaging and refined SED
  44. GRB090426: Observation for Optical counterpart from MIRO
  45. GRB090424: R-band detection (37.5 hrs post-burst), jet break?
  46. GRB 090424: MASTER-Net prompt optical limit
  47. GRB 090424: WHT ISIS spectroscopy
  48. GRB 090424 : Lulin 1m telescope optical observations
  49. GRB 090424: THO optical observations
  50. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  51. GRB 090423: Swift/BAT spectral lag results
  52. GRB 090424 optical observations
  53. GRB 090424: Liverpool Telescope observations
  54. GRB 090424: Optical observations from 1.23m CAHA
  55. Swift/UVOT observations of GRB 090424
  56. GRB 090424: MASTER-Net prompt optical observations
  57. GRB 090424: TNT optical observations
  58. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  59. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  60. GRB 090423: TNG Amici spectrum
  61. GRB 090423: GROND detection and preliminary photo-z
  62. GRB 090423: NOT z-band limit
  63. GRB 090423: Correction to NIR photometry
  64. GRB090418A Rc-band photometry
  65. GRB 090423: NIR photometry and evidence for spectral break
  66. GRB 090423: UKIRT data further analysis
  67. GRB 090423: UKIRT K-band observations
  68. GRB 090423: P60 Observations
  69. GRB 090423: Faulkes Telescope South observations
  70. GRB 090422: Liverpool Telescope possible candidate
  71. GRB 090418B: RTT150 optical observations
  72. GRB 090418A: RTT150 optical observations
  73. GRB 090422: Liverpool Telescope observations
  74. Swift-BAT trigger 349718 is not a burst
  75. GRB 090418B: GRAS002 observatios
  76. GRB 090418A: optical observations
  77. GRB 090418B: GROND observations
  78. GRB 090419: Swift/UVOT Observations
  79. GRB 090418B: Faulkes Telescope North observations
  80. GRB 090418A: Swift/UVOT Observations
  81. GRB 090419: GROND detection of afterglow candidate
  82. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  83. GRB 090419: Swift-BAT refined analysis
  84. VLA observations of short burst GRB 090417A
  85. GRB 090417B: Gemini imaging
  86. GRB 090417B: Galaxy redshift
  87. GRB 090418 OA candidate
  88. GRB 090417B: Subaru NIR Observations
  89. GRB 090417B: Liverpool Telescope observations
  90. GRB090417B: Xinglong TNT optical upper limit
  91. GRB 090417B: optical observations
  92. GRB090417B: optical observations
  93. GRB 090410: GROND upper limits
  94. Konus-Wind and Konus-RF observations of GRB 090408b
  95. GRB090408 : TAOS optical observations
  96. Swift-BAT Trigger 348781 is not a GRB
  97. Swift-BAT Trigger 348720 is not a GRB
  98. GRB 090408: Xinglong TNT optical Upper Limit
  99. GRB 090408B: MASTER II-Kourovka optical observations
  100. GRB 090407: GROND upper limits

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