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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"

4714 results found.

  1. GRB050309: CONCAM pre-trigger and trigger coincident optical
  2. GRB 050306: Confirmation of X-ray afterglow
  3. GRB 050306: further TAROT optical data
  4. GRB 050306: TAROT optical observations
  5. GRB 050306,optical observation
  6. GRB 050306: Swift-BAT detection of a long burst
  7. GRB050215B: Late-Time Swift UVOT Observations
  8. PROMPT VRcIc Observations of GRB 050223
  9. GRB050223: No Swift UVOT Detection of Afterglow Emission
  10. GRB050223: ROTSE-III Optical Observations
  11. GRB 050223 Swift/BAT detection of a burst
  12. GRB 050223: Swift XRT Position
  13. GRB 050215b: Swift XRT Observations
  14. GRB 050209 Optical observations
  15. GRB 050209: Optical observation
  16. GRB 050202: Short burst detected by Swift-BAT
  17. GRB 050129: a weak long GRB detected with INTEGRAL
  18. GRB050126: Burst Parameters Measured by BAT
  19. GRB 050126: Prompt XRT detection and localization
  20. GRB050124,optical observation
  21. GRB050124: Updated Swift XRT Position and Fluxes
  22. GRB050124: Swift-BAT position of a double-peaked burst
  23. GRB050117: Palomar WIRC Ks-band observations
  24. GRB050117b: Swift-BAT detection of a weak burst
  25. Second Epoch VLA observations of SGR 1806-20
  26. GRB041223: optical and NIR observations with REM
  27. GRB041219: Confirmed NIR Afterglow
  28. GRB 041218: Optical Observation
  29. GRB 041211: Infrared Observations
  30. GRB 041211: KAIT observations
  31. SGR 1806-20 still active
  32. GRB040929,optical observation
  33. XRF 040912, identification of CXO sources
  34. GRB040916 (= H3558): A Long XRF Localized by HETE
  35. IBAS GRB Alerts 1978-1980
  36. GRB040903 - A XRF?
  37. GRB040903, REM near-IR observation
  38. Possible GRB 040903 - further analysis
  39. Bursting activity from SGR 1806-20 detected with IBAS
  40. GRB 040730: a long GRB detected with INTEGRAL
  41. GRB040709 J,H-band observations
  42. IPN Summary of SGR1806-20 Activity in 2004
  43. GRB 040606: Optical observations
  44. Activivty of SGR 1806-20
  45. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  46. GRB 040403: Optical Observations
  47. GRB 040403 Optical Observations
  48. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  49. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  50. GRB031220: observation at Univercity of Miyazaki
  51. GRB 031220: Optical observation at Tokyo Tech
  52. IPN triangulation of GRB031214 (short/hard; very intense; small error box)
  53. GRB 2974 follow-up observations
  54. GRB 031203: Discovery of a dust echo
  55. GRB031203: ROSAT upper limits suggest XMM-S1 source as the transient
  56. GRB031203: Optical Observations
  57. GRB031203: Planned XMM-Newton observation
  58. Lulin optical follow-up observations of GRB031026
  59. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  60. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  61. IBAS detection of bursts from SGR 1806-20
  62. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  63. H2768, H2770, and H2771: Three Bursts from SGR1806-20
  64. GRB030329: RTT150 optical observations
  65. GRB030629 triangulation (Konus-Wind -- Helicon annulus)
  66. GRB030418: R optical observations
  67. GRB030528 (H2724): A long GRB localized by HETE
  68. GRB030329, Optical observations
  69. XRF030416 (=U10897): An X-Ray Flash Localized by the HETE WXM
  70. GRB030429: RTT150 optical observations, a possible host galaxy
  71. GRB030329: RTT150 optical observations and upper limit for a host
  72. GRB030329: RTT150 optical observations and upper limit for a host
  73. GRB030501 localized by INTEGRAL
  74. GRB030329: optical polarization
  75. GRB030329: 444 AAVSO Measurements
  76. GRB 030329: SARA Optical Observations
  77. IPN triangulation of GRB030414 (small error box)
  78. GRB 030329: possible color change
  79. GRB030329: Kiso B and R band observations
  80. GRB030329: More AAVSO VR obs
  81. GRB030328: R upper limit after 6 hours by MASTER
  82. GRB 030329: SARA Optical Observations
  83. GRB 030329, BVRI photometry
  84. GRB030329: final R-band light curve by MASTER
  85. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  86. GRB 030329: SARA Optical Observations
  87. GRB 030329, BRI photometry
  88. Further AAVSO V,B,R observations of GRB030329
  89. GRB 030329: SARA Optical Observations
  90. GRB 030329: Observations with ANDICAM
  91. GRB030329: further optical photometry and evidence for a light curve discontinuity
  92. GRB 030329: Correction to GCN 2056
  93. AAVSO V & R observations of GRB030329
  94. GRB 030329: optical observations
  95. GRB030329 15 GHz radio observation
  96. 030331 NOT A GRB
  97. GRB030329: R and B observations
  98. GRB030329, SPM optical observations
  99. GRB 030329: Optical Decay
  100. GRB030329: optical spectroscopy with the TNG

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