Swift Trigger: 1202749;

Presumed name: GRB 231216A

BAT	02^h 39^m 02.16^s, +33° 35′ 45.6″
position:	(39.759, +33.596 ± 180″)
XRT	02^h 39^m 05.49^s, +33° 34′ 34.6″
position:	(39.77288, 33.57629 ± 3.7″)
UVOT	No position available.
Galactic N_HI:	6.23×10²⁰ cm^-2
Galactic E(B-V):	0.093 mag

Best RA:	02^h 39^m 05.49^s	= 39.77288 d
Best Dec:	+33° 34′ 34.6″	= 33.57629 d

Gal Lat:	-24.14
Gal Long:	147.34

Sun angle:	140.34°, -9.1 hr East of Sun

Galaxies within 200 of XRT position

	RA*	Dec*	Redshift		Catalogue
7.2	39.7747	33.5750		R1=18.8, R2=19.7	USNO-B1
7.6	39.7750	33.5753			NED
15.2	39.7775	33.5781			NED
17.2	39.7776	33.5790		B1=19.4, R1=17.9	USNO-B1
19.6	39.7668	33.5783		B=21.5, R=18.4	APM-N
19.6	39.7671	33.5789			NED
21.1	39.7658	33.5769			NED
21.6	39.7657	33.5771		B2=20.7, I=17.5, R1=19.1, R2=18.8	USNO-B1
22.2	39.7655	33.5765		B1=19.0, B2=20.9	USNO-B1
23.5	39.7657	33.5788		B1=23.6, I=17.6, R2=19.4	USNO-B1
24.2	39.7762	33.5703			NED
29.3	39.7821	33.5733			NED
30.5	39.7802	33.5822		B=21.6, R=20.0	APM-N
39.7	39.7757	33.5655		B=21.5, R=20.0	APM-N
43.3	39.7633	33.5672			NED
44.2	39.7688	33.5881			NED
49.0	39.7639	33.5877		I=16.6, R2=19.8	USNO-B1
52.9	39.7742	33.5617			NED
54.4	39.7551	33.5735		B1=19.1, I=18.9, R2=19.8	USNO-B1
55.9	39.7554	33.5816		I=18.0, R2=19.6	USNO-B1
56.5	39.7719	33.5920		I=18.4, R2=19.8	USNO-B1
56.5	39.7554	33.5822		I=18.6, R1=19.3, R2=19.4	USNO-B1
56.5	39.7545	33.5796		B=21.7, R=20.0	APM-N
57.6	39.7716	33.5923		I=18.5, R2=19.7	USNO-B1
59.1	39.7553	33.5838		I=18.2, R2=19.5	USNO-B1
59.1	39.7546	33.5825		I=18.2, R2=20.1	USNO-B1
59.5	39.7663	33.5919		I=18.3, R2=19.1	USNO-B1
60.6	39.7694	33.5929		B2=20.0, I=18.5, R2=19.8	USNO-B1
60.9	39.7674	33.5926		R1=19.6, R2=19.8	USNO-B1
61.8	39.7651	33.5922		I=17.8, R1=19.5, R2=19.6	USNO-B1
62.2	39.7548	33.5847		B2=21.3, I=18.3, R2=19.7	USNO-B1
62.4	39.7644	33.5921		I=17.8, R2=18.4	USNO-B1
62.6	39.7917	33.5833			NED
63.0	39.7846	33.5618		B1=19.9, I=18.4, R1=18.6	USNO-B1
63.2	39.7850	33.5619			NED
63.3	39.7850	33.5619		B1=19.4, B2=19.8, I=17.8, R1=18.7, R2=18.2	USNO-B1
64.0	39.7849	33.5616		B=20.8, R=18.3	APM-N
65.6	39.7633	33.5927		B1=16.4, I=17.2, R2=18.1	USNO-B1
66.8	39.7519	33.5701		B1=19.8, R1=19.6	USNO-B1
67.3	39.7839	33.5926		B=21.7, R=19.1	APM-N
67.8	39.7908	33.5875			NED
69.2	39.7512	33.5698		B=20.4, R=19.1	APM-N
69.3	39.7512	33.5694			NED
69.8	39.7512	33.5693		B=20.5, R=19.2	APM-N
74.2	39.7836	33.5577		B1=19.7, B2=19.2	USNO-B1
74.4	39.7629	33.5952		B2=19.1, R2=19.7	USNO-B1
78.2	39.7550	33.5922			NED
79.7	39.7550	33.5597			NED
81.2	39.7617	33.5968		B2=20.8, R2=18.7	USNO-B1
84.4	39.7448	33.5747		B=21.6, R=19.7	APM-N
84.8	39.7447	33.5748		B1=23.3, B2=20.9, I=19.2, R2=19.8	USNO-B1
84.8	39.7608	33.5550			NED
88.0	39.7460	33.5666		B=21.6, R=19.9	APM-N
91.1	39.7742	33.5511			NED
92.9	39.7642	33.6011		B1=16.8, B2=20.8, I=18.5	USNO-B1
93.4	39.7851	33.5524		B=19.6, R=18.8	APM-N
93.7	39.7850	33.5525			NED
93.9	39.7460	33.5896		B=21.6, R=20.0	APM-N
94.2	39.7482	33.5925		I=15.5, R1=17.2	USNO-B1
94.3	39.8004	33.5639			NED
97.4	39.7600	33.5514			NED
98.8	39.7462	33.5924		R1=18.3, R2=18.4	USNO-B1
102.1	39.7447	33.5923		B2=20.9, I=18.3, R1=19.2, R2=18.7	USNO-B1
103.0	39.7983	33.5572			NED
103.7	39.7547	33.6008		I=17.8, R2=19.4	USNO-B1
103.7	39.7475	33.5958			NED
103.9	39.7441	33.5924		I=18.2, R1=19.3, R2=19.9	USNO-B1
104.1	39.7437	33.5919		I=18.5, R1=19.5, R2=19.8	USNO-B1
104.4	39.7552	33.6013		I=18.2, R2=19.5	USNO-B1
104.9	39.8026	33.5917		B2=21.2, I=19.2, R1=19.9	USNO-B1
106.1	39.7479	33.5556			NED
108.8	39.7555	33.6028		I=18.3, R1=19.0	USNO-B1
109.7	39.7503	33.5523		B=20.8, R=20.0	APM-N
109.9	39.7890	33.5489		B=21.6, R=19.9	APM-N
110.3	39.7533	33.6022		B=21.6, R=19.9	APM-N
110.3	39.7420	33.5929		I=18.0, R1=19.5	USNO-B1
110.3	39.7942	33.5514			NED
110.6	39.7501	33.5521		B1=20.0, B2=20.2, I=17.4, R1=19.6, R2=18.9	USNO-B1
110.9	39.7906	33.5492		B2=20.4, I=19.0, R2=19.8	USNO-B1
111.0	39.7544	33.6030		B2=20.0, I=18.1, R2=18.9	USNO-B1
111.4	39.7415	33.5929		I=18.5, R2=17.7	USNO-B1
112.1	39.8083	33.5667			NED
112.3	39.7376	33.5867		B=21.6, R=19.6	APM-N
112.7	39.7908	33.6036			NED
113.2	39.7621	33.6064			NED
115.0	39.7548	33.6044		R1=19.1, R2=19.5	USNO-B1
115.0	39.7346	33.5775			NED
115.5	39.7550	33.6047		B=21.6, R=19.7	APM-N
116.3	39.8113	33.5806			NED
116.8	39.7487	33.5508			NED
118.7	39.7542	33.5472			NED
120.5	39.8108	33.5869			NED
121.9	39.7866	33.6082		B=20.9, R=19.1	APM-N
123.1	39.7867	33.6086			NED
123.6	39.8062	33.5561			NED
123.7	39.7867	33.6087		B=21.3, R=19.3	APM-N
123.7	39.7365	33.5925		B1=19.1, I=18.5	USNO-B1
126.3	39.7313	33.5825			NED
128.1	39.8154	33.5772			NED
128.3	39.7917	33.6083			NED
128.6	39.7342	33.5611			NED
130.5	39.7440	33.6034		B=19.9, R=17.9	APM-N
130.7	39.7413	33.5511			NED
130.9	39.7442	33.6036			NED
131.2	39.7412	33.5511		I=17.7, R1=19.4, R2=19.1	USNO-B1
131.3	39.7688	33.5400			NED
131.8	39.7440	33.6039		B=20.1, R=18.2	APM-N
131.8	39.7333	33.5922		B2=21.2, R2=19.7	USNO-B1
133.4	39.8115	33.5947		B1=15.5, B2=17.1, I=15.3, R1=15.5, R2=16.0	USNO-B1
133.6	39.8117	33.5947			NED
133.8	39.8146	33.5631			NED
136.7	39.8008	33.6061			NED
136.9	39.7442	33.5467			NED
137.0	39.7271	33.5781			NED
137.1	39.7300	33.5632		B1=23.0, B2=20.8	USNO-B1
137.5	39.7321	33.5936			NED
138.3	39.7309	33.5603		B2=13.3, I=11.9, R1=12.0, R2=12.3	USNO-B1
138.4	39.7308	33.5603			NED
138.8	39.8050	33.5486			NED
140.1	39.7608	33.6139			NED
142.3	39.8142	33.5956			NED
142.3	39.7304	33.5583			NED
142.5	39.7537	33.5400			NED
143.2	39.8042	33.5463		B=21.6, R=19.3	APM-N
143.5	39.7296	33.5594			NED
143.8	39.8042	33.5461			NED
144.2	39.7913	33.6133		B=21.7, R=13.5	APM-N
144.2	39.7398	33.6054		B1=19.2, I=19.2	USNO-B1
144.3	39.7912	33.6133			NED
145.1	39.8087	33.6031			NED
145.1	39.7398	33.6057		B1=21.2, B2=20.9, I=18.2, R1=19.5, R2=19.8	USNO-B1
145.5	39.7913	33.6137		B=14.5, R=13.4	APM-N
145.5	39.7399	33.6059		B=21.3, R=19.8	APM-N
146.7	39.7743	33.5356		B=21.5, R=20.0	APM-N
147.4	39.7289	33.5946		B=21.6, R=20.0	APM-N
147.4	39.8217	33.5717			NED
147.7	39.8183	33.5919			NED
147.8	39.7914	33.5382		B1=23.2, I=18.4	USNO-B1
148.4	39.8146	33.5542			NED
148.6	39.8216	33.5687		B1=19.8, R1=19.7	USNO-B1
148.8	39.8146	33.5539		B=20.3, R=17.9	APM-N
149.2	39.8223	33.5716		B=20.4, R=19.9	APM-N
150.7	39.8229	33.5789			NED
151.3	39.7933	33.6147			NED
153.0	39.7229	33.5847			NED
153.4	39.7778	33.6187		B=21.6, R=19.9	APM-N
153.8	39.8071	33.5444			NED
154.4	39.8196	33.5586			NED
155.5	39.7792	33.5334		B1=14.8, B2=16.4, I=14.2, R1=14.5, R2=15.2	USNO-B1
155.8	39.7792	33.5333			NED
156.3	39.8207	33.5935		B=21.6, R=19.9	APM-N
156.7	39.8042	33.5417			NED
156.7	39.7319	33.6033		B=21.5, R=20.0	APM-N
157.1	39.7400	33.6103			NED
157.5	39.8237	33.5875			NED
157.5	39.8206	33.5581		B2=20.0, R1=19.3	USNO-B1
159.4	39.7202	33.5703		B2=21.2, R1=19.9, R2=19.4	USNO-B1
159.8	39.7442	33.6136			NED
161.0	39.8192	33.5539			NED
161.1	39.8087	33.6094			NED
161.8	39.7596	33.5328			NED
161.9	39.7594	33.5327		B=20.1, R=17.7	APM-N
162.6	39.7984	33.6162		B1=16.9, B2=18.5, I=16.0, R1=16.6, R2=16.8	USNO-B1
162.8	39.7983	33.6161			NED
163.1	39.8226	33.5579		B1=21.5, B2=20.2	USNO-B1
163.7	39.7475	33.6167			NED
165.6	39.8144	33.6066		B1=19.5, I=19.2, R1=19.9	USNO-B1
166.5	39.7946	33.5336			NED
166.9	39.7842	33.5308			NED
167.2	39.8284	33.5718		B=21.6, R=19.5	APM-N
167.9	39.7171	33.5722			NED
168.0	39.8283	33.5714			NED
168.8	39.8117	33.6103			NED
169.1	39.7338	33.5425			NED
170.2	39.8279	33.5875			NED
171.4	39.8263	33.5597			NED
171.6	39.8266	33.5598		B1=17.7, B2=19.2, I=16.8, R1=18.3, R2=18.0	USNO-B1
171.7	39.8062	33.5375			NED
173.8	39.8301	33.5688		B1=17.6, B2=20.0	USNO-B1
174.9	39.7162	33.5878			NED
175.5	39.8205	33.6047		I=19.2, R1=19.5, R2=19.7	USNO-B1
176.0	39.8175	33.5447			NED
176.2	39.7146	33.5819			NED
176.8	39.7504	33.6217		B=21.6, R=19.9	APM-N
177.0	39.7143	33.5820		B=21.6, R=19.2	APM-N
177.2	39.7583	33.6239			NED
177.9	39.8263	33.5550			NED
178.2	39.7646	33.5272			NED
178.3	39.7574	33.6241		B1=23.1, B2=20.8, I=19.2, R2=19.5	USNO-B1
178.9	39.7442	33.5328			NED
179.0	39.7979	33.6214			NED
180.0	39.7555	33.6241		B1=23.5, B2=20.9, R1=19.9	USNO-B1
180.0	39.8312	33.5644			NED
181.3	39.7350	33.6156			NED
181.4	39.8333	33.5746		B1=17.1, B2=20.6	USNO-B1
182.1	39.8336	33.5747		B1=17.6, B2=20.7	USNO-B1
182.3	39.7338	33.5375			NED
182.5	39.7779	33.5258			NED
185.3	39.8148	33.6141		B1=18.3, B2=20.9, I=18.4	USNO-B1
185.5	39.8150	33.6139			NED
186.4	39.7379	33.6192			NED
186.8	39.7584	33.6268		B1=19.6, I=18.4, R2=20.2	USNO-B1
186.8	39.7479	33.5286			NED
187.5	39.8354	33.5758		B1=17.1, B2=20.4	USNO-B1
187.6	39.8354	33.5752		B1=17.4, B2=20.8	USNO-B1
187.8	39.7805	33.5245		I=19.2, R2=19.8	USNO-B1
188.9	39.7742	33.6286			NED
189.1	39.7413	33.6217			NED
189.1	39.8152	33.6153		h=14.2, j=14.7, k=13.3	2MASS
189.2	39.8150	33.6153	0.180115		NED
189.2	39.7740	33.6288		B1=15.2, B2=16.9, I=15.7, R1=15.8, R2=16.2	USNO-B1
189.9	39.8151	33.6156		B=19.8, R=16.5	APM-N
191.0	39.7233	33.5431			NED
191.2	39.7231	33.5431		B1=18.2, B2=19.8, I=17.6, R1=17.2, R2=18.1	USNO-B1
191.3	39.8366	33.5754		B1=16.5, B2=20.6	USNO-B1
191.5	39.7379	33.5319			NED
191.8	39.8083	33.5319			NED
191.8	39.8017	33.5286			NED
193.1	39.7321	33.5350			NED
193.2	39.7196	33.5461		I=18.4, R1=19.7	USNO-B1
193.3	39.8274	33.5477		B=20.3, R=19.6	APM-N
193.5	39.7829	33.5231			NED
193.6	39.7194	33.5462		B=21.6, R=18.9	APM-N
193.7	39.7212	33.6086		B=20.6, R=19.1	APM-N
193.7	39.7963	33.6264			NED
193.8	39.7828	33.5231		B1=18.2, B2=19.6, I=17.9, R1=18.2, R2=18.3	USNO-B1
194.0	39.7117	33.5942			NED
194.3	39.7908	33.5244			NED
194.3	39.7192	33.5458			NED
194.7	39.7193	33.5458		B=20.9, R=19.0	APM-N
194.9	39.8162	33.5361			NED
196.1	39.8168	33.6167		I=18.9, R2=19.6	USNO-B1
196.2	39.8380	33.5711		B=21.6, R=19.9	APM-N
196.4	39.8379	33.5695		B1=14.8, I=18.5, R2=20.1	USNO-B1
196.7	39.7088	33.5642			NED
197.0	39.7167	33.5481			NED
197.5	39.8383	33.5703			NED
197.5	39.7164	33.5481		I=18.6, R1=19.8, R2=19.8	USNO-B1
197.7	39.8316	33.6012		B1=14.2, B2=15.4, I=13.4, R1=13.7, R2=14.3	USNO-B1
197.9	39.7085	33.5643		B=21.6, R=19.5	APM-N
197.9	39.8317	33.6014			NED
198.1	39.7271	33.6161			NED
198.2	39.8012	33.6260		B1=19.9, B2=20.5, I=18.9, R1=18.7, R2=19.2	USNO-B1
199.5	39.7095	33.5596		B=21.6, R=20.0	APM-N
199.8	39.8179	33.6172		B1=20.3, R2=19.8	USNO-B1

Queried APM-N, SDSS, PSCz, SSS, NED, 2MASSX, USNO-B1.

* RA/Dec in equinox J2000

Magnitudes depend on the catalogue. e.g. For Sloan, R is the Sloan r mag, not the Johnson R from APM, for example