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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').
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"

16159 results found.

  1. GRB 110520A: MASTER-NET optical observations
  2. GRB 110503A optical observation
  3. GRB 110503A: TAROT Calern observatory optical observations
  4. GRB 110503A optical observations
  5. GRB 110503A: optical observation in CrAO
  6. GRB 110503A: Millimeter observation from SMA
  7. GRB 110503A: Swift/UVOT Observations
  8. GRB 110503A: PAIRITEL NIR Detection
  9. GRB 110503A: redshift confirmation from TNG
  10. GRB 110503A: NOT afterglow photometry
  11. GRB 110503A: Swift detection of a burst with a bright optical counterpart
  12. GRB 110428A : X-ray afterglow confirmation
  13. GRB 110422A: optical observations in CrAO
  14. GRB 110422A: Update of Herschel FIR observation schedule
  15. GRB 110422A: optical observations in CrAO, second epoch
  16. GRB110422A: NOT optical follow-ups
  17. GRB 110422A: optical observations in CrAO
  18. GRB110422A: MITSuME Ishigakijima Optical Observation
  19. GRB 110422A: Further NOT observation
  20. GRB 110422A: Swift/UVOT Detection of optical afterglow
  21. GRB 110422A: THO optical observations
  22. GRB 110422A: TNG optical observations
  23. GRB 110422A: SAO RAS optical observations
  24. GRB 110422A: NOT optical observation
  25. GRB 110422A: MASTER earlier OT polarization observations
  26. GRB 110422A: Mondy optical observations
  27. GRB 110328A/Swift J164449.3+573451: Maidanak Optical Observation
  28. GRB 110420B: Swift/UVOT Upper Limits
  29. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  30. GRB 110420A Swift/UVOT Observations
  31. GRB 110420A: Swift detection of a burst with optical counterpart
  32. GRB110414A: MITSuME Ishigakijima Optical upper limits
  33. GRB 110414A: GROND upper limits
  34. GRB110414A: MITSuME Okayama Optical upper limits
  35. GRB 110414A: Swift/UVOT Upper limits
  36. GRB 110411A: PAIRITEL NIR Upper Limits
  37. GRB 110411A: optical limits from OSN
  38. GRB 110411A: Swift/UVOT Upper Limits
  39. GRB 110411A: MASTER prompt and follow-up optical limits
  40. GRB 110411A : Xinglong TNT OT candidate
  41. GRB 110411A: MASTER optical observations
  42. GRB 110328A / Swift J164449.3+573451: R-band Monitoring
  43. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  44. GRB 110328A / Swift J164449.3+573451: optical observations
  45. GRB 110407A: SMARTS optical limit
  46. GRB 110407A: MASTER optical observations
  47. GRB110407A: UVOT Upper Limits
  48. GRB 110407A: GROND Detection of the Optical Afterglow
  49. GRB 110407A: MITSuME Okayama and Ishigakijima Optical upper limits
  50. GRB 110407A: NOT optical observations
  51. GRB 100407A : Errata of afterglow position in GCN 11899
  52. GRB 110407A : Lulin optical afterglow detection
  53. GRB 110407A: MASTER early optical observations
  54. GRB 110402A: fading optical afterglow
  55. GRB 110328/Swift J164449.3+573451: Chandra observations
  56. GRB 110402A: LOAO Optical Observation
  57. GRB 110328A / Swift J164449.3+573451: Keck LRIS R-band photometry
  58. GRB 110328A / Swift J164449.3+573451, HST Observations
  59. GRB 110402A: optical observations in Mondy
  60. GRB 110328A / Swift J164449.3+573451: Keck/DEIMOS Optical Spectroscopy
  61. GRB 110402A: MITSuME Okayama and Ishigakijima Optical upper limits
  62. GRB 110328A/Swift J164449.3+573451: SARA-N detection
  63. GRB 110402A: early optical limit by "Pi of the Sky"
  64. GRB 110402A: further NOT observations
  65. GRB110328A/Swift J164449.3+573451: Fermi LAT Observations
  66. GRB 110402A: PAIRITEL NIR Upper Limits
  67. GRB 110402A: NOT afterglow confirmation
  68. GRB 110328A / Swift J164449.3+573451: KASINICS NIR Observation
  69. GRB 110328A / Swift J164449.3+573451: Radio-optical/NIR Astrometry
  70. GRB 110328A / Swift J164449.3+573451: Infrared transient
  71. GRB 110328A / Swift J164449.3+573451: Mondy optical observations
  72. GRB 110328A / Swift J164449.3+573451: EVLA observations of a brightening radio source
  73. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Detection in 2nd Epoch
  74. GRB 110328A / Swift J164449.3+573451: No optical variability of the optical counterpart
  75. GRB 110328A / Swift J164449.3+573451: BAT refined analysis
  76. GRB 110328A / Swift J164449.3+573451: LOAO R-band Observation
  77. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Upper Limits
  78. GRB 110328A / Swift J164449.3+573451: optical observations
  79. GRB 110328A / Swift J164449.3+573451: EVLA Detection
  80. GRB 110328A / Swift J164449.3+573451: optical spectroscopy from GTC
  81. GRB 110328A: Gemini spectroscopic observations
  82. GRB 110328A / Swift J164449.3+573451: NOT optical observations.
  83. GRB 110328A/ Swift J164449.3+573451 : Xinglong TNT Upper limit
  84. GRB / X-ray transient 110328A: MITSuME OkayamaOptical upper limits
  85. GRB 110328A / Swift J164449.3+573451: PTF Quiescent Optical Counterpart
  86. GRB / X-ray transient 110328A: Gemini optical observations
  87. GRB110318B : MOA optical upper limit
  88. GRB 101225A: revised analysis of narrow band imaging
  89. GRB 110319B: Swift/UVOT Upper Limits
  90. GRB 110318B: Swift/UVOT Upper Limits
  91. GRB 110319A: Swift/UVOT Detection
  92. GRB 110315A: RTT150 optical observations
  93. GRB 110315A: Swift/UVOT Upper Limits
  94. GRB 110315A: MASTER early optical observations
  95. GRB110312A: MITSuME Okayama Optical upper limits
  96. GRB 110312A: RTT150 optical observations
  97. GRB 110312A: Swift/UVOT Upper Limits
  98. GRB 110312A: GROND Upper Limits
  99. GRB 110305A: REM detection of a possible NIR afterglow
  100. GRB110305A: MITSuME Ishigakijima Optical upper limits

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