Integral - SPI

Calibrations results
====================

SPI / Bruyère Calibration First Results
---------------------------------------

Data reduction (Imaging of the (60)Co beetween 1100 and 1400 keV).

Pixel size : 0.2*0.2 ° - Imaging method : IROS

Session of 2001/04/10 and 2001/01/11

'''''''''''''''''''''''''''''''''''''''

image:images/calibration/mini1.jpg[width=300,align="right"]

[horizontal]
Pointing:: 31
Start Time:: 21:53
End Time:: 22:14 
Spi Position :: 0
Recover Position (alpha, delta):: (0.001, -0.006)
Nb of Sigma:: 431

''''''''''''''''''''''''''''''''''''''''

[format="csv",options="header", cols="10,10,10,10,10,10,10"]
|=======================================================================================
Pointing, Start Time, End Time, SPI Pos, Recover Position, Nb of Sigma, Significance Map
35, 23:33, 23:55, 359.5, 0.492, 0.008, 392
36, 23:57, 00:19, 359, 1.053, 0.014, 387
37, 00:24, 00:46, 358, 2.042, -0.06, 374
38, 00:51, 01:12, 356, 3.972, 0.027, 379
|=======================================================================================

image:images/calibration/mini1.jpg[]
image:images/calibration/mini2.jpg[]
image:images/calibration/mini3.jpg[]
image:images/calibration/mini4.jpg[]
image:images/calibration/mini5.jpg[]

N.B. : Normally, to obtain sky images with SPI, we used the dithering technique.
Nevertheless, we have build images pointing by pointing which explain the apparition of the numerous ghosts.
There is also a problem in the transfert function of SPI due to the absorption of the central mask element.

Imaging with the (60)Co source using dithering
----------------------------------------------

We have used 14 pointings on the (60)Co with the source position varying form 0 to 8° from the telescope axis.

Then we build an observation using these 14 pointings.

Images obtained using different method : modified cross correlation, maximum entropy (memsys5) 
and IROS are presented on the next figures (pixel size : 0.2°*0.2°).

1. Maximun entropy
~~~~~~~~~~~~~~~~~~

Source located at (0°,0°), 
integrated significance on a radius of 0.5° : 604 sigma (pixel size : 0.5°*0.5°).

image:images/calibration/1.jpg[width=400,align="center"]

2. Correlation of the mask with the detector shadowgram
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

image:images/calibration/2.jpg[width=400,align="center"]
	
3. IROS
~~~~~~~

We obtained for IROS a source of (-0.029°, + 0.007°) with 1117 sigma, 
the following map is the residual significance.

image:images/calibration/3.jpg[width=500,align="center"]

Imaging with the (24)Na source using dithering
----------------------------------------------

We have used 19 pointings on the (24)Na.

Image resolution : 0.2°*0.2° , image size : 101*101 pixels, centered at (0°*0°).

Source intensity : 671 sigma

image:images/calibration/4.jpg[]
	
Imaging with the (137)Cs source using dithering, between 600 and 700 keV
------------------------------------------------------------------------

We have used 66 pointings on the (137)Cs.

Image resolution : 0.2°*0.2° , image size : 101*101 pixels, 
centered at (0°*0°).

Source intensity : 1912 sigma

The source position found is (-0.047°, -0.018°)

image:images/calibration/5.jpg[]

Position of the (137)Cs source for different pointings.
-------------------------------------------------------

image:images/calibration/6.jpg[align="left"]


Pointing number : 86 

Spi Axe : 358.0° - Rotation : 0°

Source position found : (-2.052°, -0.014°)

Flux : 0.45 (arbitrary unit)

'''''''''''''''''''''''''''''''''''''''''''''

image:images/calibration/7.jpg[align="left"]

Pointing number : 223 

Spi Axe : 358.5° - Rotation : 30°

Source position found : (1.436°, -0.847°)

Flux : 0.45 (arbitrary unit)

'''''''''''''''''''''''''''''''''''''''''''''

image:images/calibration/8.jpg[align="left"]

Pointing number : 240 

Spi Axe : 2.0° 

Rotation : 30°

Source position found : (-1.678°, 1.005°)

Flux : 0.44 (arbitrary unit)

'''''''''''''''''''''''''''''''''''''''''''''

image:images/calibration/9.jpg[align="left"]

Pointing number : 241 

Spi Axe : 4.0° 

Rotation : 30°

Source position found : (-3.4004°, 1.987°)

Flux : 0.44 (arbitrary unit)


Bruyeres Le Chatel - Calibration Results
----------------------------------------

image:images/calibration/10.jpg[width=500]

''''''''''''''''''''''''''''''''''

image:images/calibration/11.jpg[width=500]

''''''''''''''''''''''''''''''''''

image:images/calibration/12.jpg[width=500]

''''''''''''''''''''''''''''''''''

image:images/calibration/13.jpg[width=500]

''''''''''''''''''''''''''''''''''

image:images/calibration/14.jpg[width=500]