Theoretical Elliptical Galaxies with analysis

Each elliptical galaxy is simulated with the given parameters and the resulting analysis is shown next to it

All images are 512 by 512 pixels

Part 1: No noise, only galaxies
common parameters to all:

gain	rdnoise	poisson	seeing radius/scale (pixels)	moffat param	distanc	magzero	model
1 e/ADU	0 electrons	no	1	beta = 2.5	1	7	devauc

Egal 1:

center	mag	rad	ar	pa	exptime
(200,200)	-5	15	4	4	1

this ar gives e = 0.97
     

I had to manually enter the center position for the ellipse task, as it said it couldn't find it



Egal2:

center	mag	rad	ar	pa	exptime
(200,100)	-8	1	2	44	1

e = 0.87
     






Egal 3:

center	mag	rad	ar	pa	exptime
(210,150)	-15	0.5	0.1	94	1

e = ??
     





Egal 4:

center	mag	rad	ar	pa	exptime
(200,200)	-5	1.5	1.5	42	1

e=XXX
     




Part 2: Noise and Galaxies
common parameters to all:

gain	rdnoise	poisson	seeing radius/scale (pixels)	moffat param	distanc	magzero	model
1 e/ADU	1 electron	no	1	beta = 2.5	1	7	devauc

Egal5:

center	mag	rad	ar	pa	exptime
(200,200)	-5	1.5	1.5	42	1

e=0.33
     



Egal6:

center	mag	rad	ar	pa	exptime
(200,200)	-5	3	1.5	10	1

e=0.33
     



Egal7:

center	mag	rad	ar	pa	exptime	background	read noise
(200,200)	-15	5	1.5	10	1	100	5 e

e=0.33
     





Egal8:

center	mag	rad	ar	pa	exptime	background	read noise	Poisson noise
(200,200)	-15	5	1.5	10	1	100	5 e	yes

e=0.33
     





Egal9:

center	mag	rad	ar	pa	exptime	background	read noise	Poisson noise
(200,200)	-15	5	1.5	10	1	10	5 e	yes

with Star1.dat: 1,000 stars, from -7 to 0 by a power law w/ coefficient 0.6
e=0.33
     




Egal10:

center	mag	rad	ar	pa	exptime	background	read noise	Poisson noise
(200,200)	-15	5	1.5	10	1	10	5 e	yes

with Star2.dat: 10,000 stars, from -7 to 4 by a power law w/ coefficient 0.6
e=0.33
     





Egal11:

center	mag	rad	ar	pa	exptime	background	read noise	Poisson noise
(200,200)	-15	5	2	10	1	10	5 e	yes

with Star3.dat: 10,000 stars, from -7 to 4 by a power law w/ coefficient 0.6
ar = 2 means this elliptical should have e = 0.5
     
                                                                                                                                                      bigger than SMA ( radius ) = 65 didn't converge in the ellipse package





Applying ring median smoothing [ir = 2, or = 5] to the image, we do the same ellipse analysis on it:
     







smoothing on ir = 1, or = 3
     







smoothing on ir = 3, or = 8
     



Egal12
Generating 2 galaxies together/near each other:
(using star4.dat) left one is identical to above, right one is centered on (300,200), has PA = 100-deg, is larger (R = 15) and rounder (ratio = 1.25, e=0.2).


                                                started on (200,200) [left galaxy] :                                                                                             started on (300,200) [right galaxy]
     


Egal13
Still making 2 galaxies, but now with 100,000 field stars, too, in a power law (0.6) from -11 to 4. (star5.dat):
e1 = 0.5, e2 = 0.2     PA1 = 10, PA2 = 100 (-80)

                                                started on (200,200) [left galaxy] :                                                                                             started on (300,200) [right galaxy]
      



Move on to starting REAL data (NGC4473)


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