• Go back to Ehsan's main page: Challenger

---

Sample Galaxies

• 144 galaxies were selected with size in the range 0 and 2 arcmin. The size distribution is chosen to be uniform.
• The photometry results for both SDSS and Pan-STARRS are displayed in the below table. (please scroll down)
• To make a better comparisons, all of those galaxies with noisy images, or bad data were removed. 19 galaxies were then removed. These information and the results for these galaxies are available on the below table. These galaxies are PGC [40761,23519,64552,62651,60049,24469,90968,61254,4010299,38457,142843,91191,39833,48409,1672298,1305231,61220,60436,53891].
• After removing these galaxies, we are left with 125 galaxies.

• The comparison between SDSS and Pan-STARRS photometry results. In most cases it's obvious that Pan-STARRS photometry turns out fainter magnitudes. It's due to the background oversubtraction, and unfortunately this does not depend on the size of the galaxy.

---

• The same plots for r-band

---

• This plot compare g-r colors in terms of size. No correlation with galaxy size is apparent. The color discrepancy is roughly around 0.1 mag. Since SDSS photometry accuracy is around 0.05 mag at best (color accuracy of ~0.07), then this plot indicates a color accuracy of about 0.15 mag at best.
• Also one has to note that out of 144 galaxies 19 (13%) have been removed due to data quality (mostly Pan-STARRS).

---

---

• This table summarizes all the results.

no

PGC

d25

g.sdss

r.sdss

profile

images

note-sdss

*

g.ps

r.ps

profile

images

note-Pan-STARRS

*

1	45947	1.95	13.28	12.55	​profile	​images			*	13.31	12.62	​profile	​images			*
2	21684	1.95	14.13	13.59	​profile	​images			*	14.13	13.57	​profile	​images			*
3	34718	1.91	13.82	13.36	​profile	​images			*	13.91	13.43	​profile	​images			*
4	43863	1.91	14.32	13.48	​profile	​images			*	14.37	13.54	​profile	​images		saturated center	*
5	34913	1.91	13.95	13.09	​profile	​images			*	13.89	13.04	​profile	​images			*
6	30818	1.91	13.96	13.41	​profile	​images			*	14.15	13.59	​profile	​images			*
7	41958	1.91	13.50	12.79	​profile	​images			*	13.53	12.86	​profile	​images			*
8	37429	1.91	12.50	11.90	​profile	​images			*	12.66	12.07	​profile	​images			*
9	41020	1.86	14.73	14.48	​profile	​images			*	14.87	14.57	​profile	​images			*
10	19652	1.82	14.75	14.05	​profile	​images			*	14.71	14.09	​profile	​images			*
11	9510	1.82	14.74	14.00	​profile	​images			*	14.65	14.00	​profile	​images			*
12	43517	1.82	14.14	13.38	​profile	​images			*	14.13	13.46	​profile	​images		saturated center	*
13	47971	1.82	13.30	12.72	​profile	​images			*	13.32	12.78	​profile	​images			*
14	23169	1.82	14.26	13.49	​profile	​images			*	14.22	13.47	​profile	​images			*
15	43837	1.86	12.75	12.23	​profile	​images			*	12.85	12.33	​profile	​images		background oversubtraction	*
16	37723	1.86	12.89	12.45	​profile	​images			*	13.05	12.65	​profile	​images		bad background	*
17	39366	1.74	13.84	13.48	​profile	​images			*	13.88	13.48	​profile	​images			*
18	52167	1.78	14.35	13.98	​profile	​images			*	14.45	14.01	​profile	​images		g-band background issue	*
19	61220	1.7			​profile	​images			*	14.10	13.56	​profile	​images		saturated center	*
20	12514	1.7	16.07	15.69	​profile	​images			*	16.14	15.91	​profile	​images			*
21	21918	1.7	14.51	13.77	​profile	​images			*	14.43	13.78	​profile	​images			*
22	54262	1.78	14.87	14.50	​profile	​images			*	14.93	14.60	​profile	​images			*
23	32786	1.74	13.69	13.13	​profile	​images			*	13.92	13.30	​profile	​images		saturated cneter	*
24	50897	1.7	13.87	13.33	​profile	​images			*	14.04	13.45	​profile	​images		saturated center	*
25	49995	1.66	13.09	12.25	​profile	​images			*	13.24	12.47	​profile	​images		saturated center	*
26	60436	1.62			​profile	​images			*			​profile	​images			*
27	70020	1.66	13.72	13.05	​profile	​images			*	13.83	13.18	​profile	​images		background oversubtraction	*
28	35621	1.62	14.02	13.51	​profile	​images			*	14.04	13.64	​profile	​images		saturated center	*
29	10029	1.62	13.90	13.02	​profile	​images			*	13.97	13.14	​profile	​images			*
30	53332	1.62	14.21	13.56	​profile	​images			*	14.16	13.57	​profile	​images			*
31	40516	1.66	12.29	11.78	​profile	​images			*	12.60	12.12	​profile	​images		saturated center	*
32	59634	1.66	14.34	13.61	​profile	​images			*	14.35	13.63	​profile	​images		g-band uncertain	*
33	11941	1.51	13.71	12.91	​profile	​images			*	13.69	13.02	​profile	​images		saturated center	*
34	50853	1.51	14.64	13.98	​profile	​images			*	14.69	14.00	​profile	​images			*
35	43341	1.51	14.15	13.85	​profile	​images			*	14.56	14.08	​profile	​images			*
36	25781	1.55	14.35	13.88	​profile	​images			*	14.35	13.89	​profile	​images			*
37	27232	1.51	13.29	12.71	​profile	​images			*	13.30	12.77	​profile	​images			*
38	35405	1.58	13.31	12.87	​profile	​images			*	13.39	12.94	​profile	​images			*
39	46321	1.58	13.53	12.94	​profile	​images			*	13.68	13.09	​profile	​images			*
40	23646	1.55	14.34	13.65	​profile	​images			*	14.30	13.68	​profile	​images		saturated center	*
41	66622	1.48	14.33	13.57	​profile	​images			*	14.32	13.57	​profile	​images		a few pixel at the center saturated	*
42	40761	1.48	14.97	14.76	​profile	​images		low luminosity - high uncertainty	*	15.22	15.20	​profile	​images		i-band data uncerain - artifact	*
43	10542	1.41	14.69	13.91	​profile	​images			*	14.55	13.85	​profile	​images			*
44	6627	1.41	15.12	14.29	​profile	​images		done	*	15.11	14.32	​profile	​images			*
45	26871	1.45	15.92	15.35	​profile	​images			*	16.05	15.41	​profile	​images			*
46	49489	1.48	12.58	11.91	​profile	​images			*	12.57	11.94	​profile	​images			*
47	47680	1.45	14.72	14.17	​profile	​images			*	14.73	14.16	​profile	​images			*
48	22827	1.41	13.61	13.16	​profile	​images			*	13.64	13.17	​profile	​images			*
49	50017	1.32	14.93	14.13	​profile	​images			*	15.06	14.16	​profile	​images		saturated center	*
50	59498	1.32	13.94	13.46	​profile	​images			*	13.97	13.49	​profile	​images			*
51	23519	1.35	1.93	1.71	​profile	​images		sounds noisy	*	14.16	13.61	​profile	​images		intense g-ban masking	*
52	47935	1.35	15.52	14.75	​profile	​images			*	15.54	14.81	​profile	​images			*
53	11074	1.35	14.56	13.94	​profile	​images			*	14.54	13.92	​profile	​images			*
54	51155	1.32	14.11	13.39	​profile	​images			*	14.16	13.42	​profile	​images			*
55	26765	1.35	14.36	13.80	​profile	​images			*	14.45	13.80	​profile	​images			*
56	6982	1.32	13.57	12.84	​profile	​images		done	*	13.62	12.91	​profile	​images			*
57	49838	1.29	14.58	13.97	​profile	​images			*	14.64	14.03	​profile	​images			*
58	55349	1.23	14.81	14.03	​profile	​images			*	15.01	14.19	​profile	​images			*
59	22381	1.23	13.57	12.85	​profile	​images			*	13.52	12.82	​profile	​images			*
60	55475	1.23	15.00	14.48	​profile	​images			*	14.99	14.50	​profile	​images		saturated center	*
61	39113	1.29	15.30	14.95	​profile	​images		noisy uncertain z-band data	*	15.51	15.21	​profile	​images			*
62	34692	1.26	13.33	12.90	​profile	​images			*	13.38	12.99	​profile	​images			*
63	64552	1.26			​profile	​images			*	14.07	13.46	​profile	​images		messy - heavy masking	*
64	59735	1.2	14.14	13.75	​profile	​images			*	14.25	13.92	​profile	​images		g-band, llosing light ... background oversubtraction in all bands (probable)	*
65	151574	1.1	14.93	14.15	​profile	​images			*	14.89	14.15	​profile	​images			*
66	50210	1.1	14.43	14.24	​profile	​images			*	14.72	14.44	​profile	​images			*
67	47305	1.12	15.20	14.62	​profile	​images			*	15.20	14.64	​profile	​images			*
68	22880	1.12	14.90	14.30	​profile	​images			*	14.90	14.35	​profile	​images			*
69	12775	1.15	16.23	15.48	​profile	​images			*	16.17	15.37	​profile	​images			*
70	62651	1.1	14.78	13.66	​profile	​images		very crowded	*	14.68	13.78	​profile	​images		super messy, crowded field, tons of foreground stars	*
71	56366	1.1	15.08	14.67	​profile	​images			*	15.07	14.68	​profile	​images			*
72	50262	1.1	13.78	13.52	​profile	​images			*	14.04	13.79	​profile	​images			*
73	32708	1.07	15.04	14.66	​profile	​images			*	15.32	14.70	​profile	​images			*
74	37740	1.0	15.87	15.68	​profile	​images			*	16.04	15.73	​profile	​images			*
75	53864	1.0	15.54	15.26	​profile	​images		no good z and u-bands	*	15.47	15.22	​profile	​images			*
76	40408	1.05	14.86	14.45	​profile	​images			*	14.90	14.52	​profile	​images			*
77	507	1.02	14.87	14.12	​profile	​images		Done	*	14.89	14.16	​profile	​images			*
78	33869	1.05	14.99	14.28	​profile	​images			*	14.99	14.29	​profile	​images			*
79	60049	1.07	15.71	15.03	​profile	​images		bright star at the center ... probably missing light	*	15.61	15.01	​profile	​images			*
80	24469	1.0	14.67	14.12	​profile	​images		bright nearby galaxy, fuccy light around the galaxy. ... probably a disturbed system ... ejected gas !!!!?	*	14.65	14.08	​profile	​images		bright close galaxy ...	*
81	23465	0.98	15.13	14.80	​profile	​images			*	15.12	14.85	​profile	​images			*
82	71288	0.98	14.39	13.73	​profile	​images			*	14.40	13.86	​profile	​images			*
83	58514	0.91	16.36	15.53	​profile	​images			*	16.16	15.45	​profile	​images			*
84	49137	0.93	14.56	14.08	​profile	​images			*	14.57	14.09	​profile	​images		background oversubraction in g-band	*
85	90968	0.91	5.80	5.55	​profile	​images		noisy, seems to be super bright (weird !!!)	*	16.43	16.11	​profile	​images		super uncertain, bad background	*
86	61254	0.91	15.02	14.25	​profile	​images		u-band not good, other bands uncertain, z-band seems to be Ok though ... the accuracy 0.1 mag	*	15.29	14.60	​profile	​images		intense masking	*
87	53891	0.95	18.38	17.29	​profile	​images			*	15.02	14.55	​profile	​images		very bright star next to the galaxy - super uncertain	*
88	59376	0.91	14.64	13.99	​profile	​images			*	14.61	13.97	​profile	​images			*
89	54400	0.85	15.85	15.22	​profile	​images			*	15.83	15.21	​profile	​images			*
90	25111	0.83	14.68	14.36	​profile	​images			*	14.79	14.45	​profile	​images			*
91	68009	0.89	15.34	14.56	​profile	​images			*	15.24	14.51	​profile	​images			*
92	91489	0.89	16.28	15.54	​profile	​images			*	16.23	15.52	​profile	​images			*
93	6678	0.89	15.41	14.79	​profile	​images			*	15.48	14.78	​profile	​images			*
94	24977	0.85	15.26	14.57	​profile	​images			*	15.27	14.56	​profile	​images		loosing light on the edges !!!	*
95	24012	0.85	14.75	14.35	​profile	​images			*	14.76	14.33	​profile	​images			*
96	67626	0.89	14.52	13.91	​profile	​images			*	14.55	13.97	​profile	​images			*
97	23026	0.78	14.24	13.81	​profile	​images			*	14.27	13.80	​profile	​images			*
98	47966	0.74	15.31	14.68	​profile	​images			*	15.21	14.64	​profile	​images			*
99	4010299	0.74	16.45	16.05	​profile	​images		looks like a blob ... probably not good for distance measurments	*	16.52	16.23	​profile	​images			*
100	22918	0.78	14.64	13.89	​profile	​images			*	14.62	13.91	​profile	​images			*
101	60271	0.72	16.14	15.84	​profile	​images			*	16.09	15.86	​profile	​images			*
102	58700	0.78	16.89	16.34	​profile	​images			*	16.90	16.34	​profile	​images			*
103	91110	0.71	16.79	16.33	​profile	​images			*	16.85	16.52	​profile	​images			*
104	52350	0.79	15.15	14.55	​profile	​images			*	15.15	14.51	​profile	​images			*
105	91488	0.68	16.88	16.37	​profile	​images			*	16.88	16.36	​profile	​images			*
106	43840	0.68	15.44	14.89	​profile	​images			*	15.48	14.94	​profile	​images			*
107	23033	0.63	16.61	15.92	​profile	​images			*	16.88	16.16	​profile	​images		g-band has problems	*
108	55844	0.65	14.88	14.18	​profile	​images			*	14.80	14.13	​profile	​images			*
109	40943	0.6	15.32	14.94	​profile	​images			*	15.40	14.99	​profile	​images			*
110	38457	0.62	15.62	15.23	​profile	​images			*	15.57	15.56	​profile	​images		very bad data	*
111	91516	0.66	16.71	16.10	​profile	​images			*	16.58	16.25	​profile	​images			*
112	67891	0.65	15.75	15.13	​profile	​images			*	15.66	15.07	​profile	​images			*
113	51293	0.58	15.54	15.13	​profile	​images		super face-on	*	15.41	14.99	​profile	​images			*
114	214939	0.58	16.81	16.14	​profile	​images			*	16.83	16.33	​profile	​images			*
115	22218	0.59	15.69	15.26	​profile	​images			*	15.67	15.30	​profile	​images			*
116	91009	0.5	17.28	16.78	​profile	​images			*	17.24	16.83	​profile	​images			*
117	51230	0.58	15.68	15.23	​profile	​images			*	15.62	15.18	​profile	​images			*
118	30263	0.55	13.94	13.47	​profile	​images			*	13.94	13.48	​profile	​images			*
119	39038	0.56	15.54	15.00	​profile	​images			*	15.50	14.98	​profile	​images			*
120	51144	0.56	15.66	15.31	​profile	​images			*	15.74	15.34	​profile	​images			*
121	165902	0.47	15.82	15.06	​profile	​images			*	15.75	15.04	​profile	​images			*
122	169959	0.49	16.59	16.13	​profile	​images			*	16.75	16.31	​profile	​images			*
123	100776	0.4	15.58	14.91	​profile	​images			*	15.54	14.89	​profile	​images			*
124	33529	0.48	15.85	15.47	​profile	​images		z-band magnitude Not reliable !	*	16.07	15.49	​profile	​images			*
125	22630	0.4	15.96	15.45	​profile	​images			*	15.96	15.50	​profile	​images			*
126	90854	0.49	17.19	16.67	​profile	​images			*	17.17	16.73	​profile	​images		bad g-band data	*
127	139387	0.42	16.95	16.50	​profile	​images			*	16.96	16.49	​profile	​images			*
128	3460270	0.48	16.43	15.93	​profile	​images			*	16.51	15.99	​profile	​images			*
129	49294	0.39	15.21	14.76	​profile	​images		bad U-band magnitude	*	15.39	14.84	​profile	​images			*
130	38963	0.35	16.19	15.80	​profile	​images			*	16.10	15.88	​profile	​images			*
131	140542	0.35	16.14	15.72	​profile	​images			*	16.06	15.76	​profile	​images			*
132	142843	0.38	16.64	16.22	​profile	​images		There is an edge-on nearby galaxy. There is chance tht the HI measurments are confused. Not recommended for distance measurements	*	16.64	16.25	​profile	​images			*
133	1331483	0.37	16.03	15.63	​profile	​images			*	15.94	15.57	​profile	​images			*
134	39342	0.37	15.19	14.90	​profile	​images			*	15.26	14.93	​profile	​images			*
135	23531	0.35	16.53	16.16	​profile	​images			*	16.61	16.16	​profile	​images			*
136	91191	0.35	4.43	4.51	​profile	​images		bad image, good photometry	*	16.69	16.51	​profile	​images			*
137	1701087	0.28	16.53	16.43	​profile	​images		No good z-band profile	*	16.63	16.45	​profile	​images			*
138	39833	0.2	16.78	16.47	​profile	​images		bad z/u bands	*	17.83	17.48	​profile	​images		super uncertain - bright star in the field . bad data	*
139	48409	0.28	16.07	15.76	​profile	​images		bright galaxy next to the center,bad z-band, gri magnitudes seems to be ok	*	16.21	15.81	​profile	​images		bright objsct near the center ... probability of contamination	*
140	41716	0.28	15.37	14.86	​profile	​images			*	15.56	14.94	​profile	​images			*
141	1672298	0.28	18.04	17.14	​profile	​images		super faint, no morphology can be determined	*	17.77	17.10	​profile	​images		bad SB profile ....	*
142	1305231	0.27	16.53	16.49	​profile	​images		No good magnitude .. next to a bright star ...	*	17.20	17.04	​profile	​images		Terrible	*
143	35380	0.2	14.06	13.75	​profile	​images			*	14.19	13.84	​profile	​images			*
144	91775	0.26	16.27	15.81	​profile	​images			*	16.25	15.82	​profile	​images			*