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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"

3868 results found.

  1. XRF040701: First-Epoch Chandra Observations
  2. GRB040709 J,H-band observations
  3. GRB040706:observation at University of Miyazaki
  4. IPN Summary of SGR1806-20 Activity in 2004
  5. SGR 1806-20: no IR variability of the proposed counterparts
  6. SGR 1806-20, potential NIR counterpart
  7. MASTER: HETE Alert 3274 optical observation
  8. Activivty of SGR 1806-20
  9. IBAS GRB Alerts n.1785 to 1791
  10. GRB 040422: a long GRB detected with INTEGRAL
  11. Summary of recent bursts from SGR 1806-20 detected by INTEGRAL
  12. IBAS GRB Alert 1694
  13. short hard GRB 040322
  14. IBAS GRB alerts 1679, 1680, 1681
  15. IBAS results on a burst from SGR1806-20
  16. RXTE GRB040229 optical observation: no candidate
  17. GRB031220: observation at Univercity of Miyazaki
  18. GRB 031220: Optical observation at Tokyo Tech
  19. GRB 031203: Discovery of a dust echo
  20. GRB031203: K' Photometry of the likely GRB host
  21. XRF031109 (=H2919): A very long XRF localized by HETE
  22. IPN triangulation of GRB031026B (large error box)
  23. IBAS alert 1180 refers to a burst from SGR 1806-20
  24. Ongoing Bursting Activity from SGR 1806-20 detected with IBAS
  25. SGR1806-20 bursts on 031008. Helicon detection and small error box.
  26. SGR 1806-20 bursts with INTEGRAL and IBAS announcement on Soft Gamma-Ray Repeaters
  27. XRF 030723: Subaru Optical Observations
  28. A burst from SGR 1806-20 detected with IBAS
  29. IPN triangulation of GRB030926 (short/hard; large error box)
  30. GRB030913: AAVSO optical observations
  31. IBAS detection of bursts from SGR 1806-20
  32. Radio Observations of SGR1806-20
  33. INTEGRAL ToO OBSERVATIONS OF SGR1806-20: CALL FOR CORRELATED OBSERVATIONS
  34. Summary of recent IPN and HETE detections of SGR bursts
  35. Clarification of GCN 2354 on SGR1806-20
  36. IPN detection of continued activity from SGR1806-20
  37. 030813 SGR event (Konus-Wind observation)
  38. SGR 1808-20 (=H2802): A Possible new SGR
  39. IPN triangulation of GRB030721 (large error box)
  40. GRB030723: Upper limits from historical observations
  41. XRF030723, optical observations
  42. SGR 1806-20, submm observations
  43. RXTE PCA Observations of SGR1806-20 Region
  44. IPN triangulation of GRB030715 (two large error boxes)
  45. GRB030329: RTT150 optical observations
  46. GRB030329, optical observation in May
  47. HETE detection of burst from SGR1806-20
  48. IPN triangulation of GRB030606 (two alternate error boxes)
  49. GRB 030528: tentative NIR counterpart
  50. GRB 030329/SN 2003dh: Jitter Episode
  51. GRB030519B (=H2716): A Long, Bright GRB Localized by the HETE WXM
  52. GRB 030329: Optical limit (contemporaneous imaging)
  53. IPN triangulation of GRB030509 (single error box)
  54. GRB030429, refiend optical brightness
  55. GRB 030329: Optical limit (contemporaneous photography)
  56. GRB030429 (=H2695): A Long GRB Localized by the HETE WXM and SXC
  57. GRB 030329 Optical Observations
  58. GRB030328, optical observation
  59. GRB030429: Optical Observations
  60. GRB030329 observed as a sudden ionospheric disturbance (SID)
  61. OT GRB 030329: early UBVRcIc spectral evolution
  62. GRB030329, UBVRI polarimetry, R-polarization
  63. OT GRB 030329: early spectrum
  64. IPN triangulation of GRB030413 (small error box)
  65. GRB030329: Near Infrared Observations at Gunma
  66. GRB030329: Kiso B and R band observations
  67. GRB030328: R upper limit after 6 hours by MASTER
  68. GRB030329: final R-band light curve by MASTER
  69. GRB030329: optical observations at Tokyo Tech
  70. Further AAVSO V,B,R observations of GRB030329
  71. GRB 030329: Additional Mt. Laguna Optical Observations
  72. GRB 030329: Observations with ANDICAM
  73. GRB030329: Optical observations
  74. GRB 030329: Correction to GCN 2056
  75. GRB 030329: optical observations
  76. GRB 030328, optical photometry
  77. GRB030329: R band light curve by MASTER
  78. GRB030329 - near contemporaneous optical limits from CONCAM
  79. GRB 030329: Optical pre-Imaging
  80. GRB 030329: visual observations
  81. GRB 030329: OT B and R photometry, decline rate
  82. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  83. RXTE detection of GRB 030329 afterglow
  84. GRB 030329: Optical Afterglow Observations
  85. GRB 030328 Optical Observations
  86. GRB030328: Decay index
  87. GRB 030329: OT candidate
  88. GRB030328: optical spectroscopy at TNG
  89. GRB030328: optical photometry at the TNG
  90. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  91. IPN triangulation of GRB030326 (single small error box)
  92. GRB 030323: SARA Optical Observations
  93. IPN triangulation of GRB030325 (two small error boxes)
  94. GRB030323: V, R, I photometry
  95. GRB 030227: fading of candidate optical afterglow 'S1-A'
  96. GRB 030227, possible optical counterpart of XMM-Newton source
  97. GRB030227 - faint tentative OT candidate
  98. XMM-Newton observation of GRB030227
  99. GRB 030227: Kyoto optical observation
  100. GRB030227: refined INTEGRAL position

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