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ecsnoopy 2.0 tutorial
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Tutorial ecsnoopy

Version 2.0

Parameter files

Instrument parameter files can be splitted (typically grouped by site). They need to have the extension .instr   (replace snoopy.default). Example.

Photometric zero point can be also splitted in separate files. Extension .zp (replace photo.log). Example

If not available for instrument, use dummy ZP and ignore color term correction

Extinction coefficients can also be splitted in separate files. Extension .kext (replace extinction.dat). Example

If not available for site, skip extinction correction.

Parameter files are searched with the following order:

  1. script directory (.../ecsnoopy/ecsnoopy/instr for .instr,.zp,.kext)
  2.  user directory identified with the shell variable snprivate (eg. export snprivate=/home/enrico/mysnoopypar/ )
  3.  the working directory


Special keyword:

If a keyword saturat and/or datamin in present in the image fits file, its value will supersedes that in the *.instr file

Target list 

SN coordinate(s) file can contain many objects including multiple objects in the field and multiple fields. One object per line identified by a name. Additional target(s) in the same line are intended as SN companion star(s). Example

Command list

eclist                         list and select files

---  Prepare images

ecmjd                          Compute MJD and update file keyword

ecastroauto             Automatic astrometric calibration

ecastro                       Manual astrometric calibration

ecseeing                        Measure seeing

ecmask                         Build mask for bright stars (used by ecsndiff)

ecdither                       Combine dithered images.

---  Measure SN mag

ecsnfit                        SN psf fit: run ecpsf, ecfit, ecart on list of images

ecsndiff                        Produce image difference and measure SN mag with psf fit

ectemplate                 Download templates for given position from PS1, ZFT, SkyMapper,


---  Calibration

ecph                           Measure standard field and derive zero points

ecrefstar                      Calibrate local reference stars

eczp                           Measure photometric zero point with reference to local or remote


ecsncal                        Derive SN (and companion stars) apparent magnitude

---  Service

ecfindingchart                 Create finding chart with identification of local standards (TBD)

Basic run

eclist @list                        - in case there are ERROR  they need to be addressed

ecsnfit @list sn.coo          - if psf fails , check seeing

eczp @list ps1 -i               - interactive mode suggested

ecsncal  @list

Examples and templates

Example of *.instr file.

Section is defined by [TELESCOPE,INSTRUME]. Only the first word of the keyword content is used.

There can be multiple filter keywords, separated by commas.


site:        ASIAGO                    OPTIONAL default extinction coefficient 0. for all bands

saturat:   60000.

datamin :  0                              OPTIONAL  default INDEF

epadu:     0.9                            OPTIONAL  default 1.0

ron:         7.8                             OPTIONAL  default 4.0

scale:      0.506

object:      OBJECT                  OPTIONAL  

exptime:   EXPTIME

mjd:          MJD

dateobs:   DATE-OBS              OPTIONAL

airmass:   AIRMASS                OPTIONAL  default 1.0

filter:        FILTER1,FILTER2    

open:      NONE,r                     OPTIONAL

seeing:    SEEING

UBVRI:     U,B,V,R,i

ugriz:        u-Sloan,g-Sloan,r-Sloan,i-Sloan,z-Sloan

Example of *.zp file

### 1.82m,AFOSC 2020-04-02   58951.082

U UB 19.929 0.011 0.196 0.018

B BV 22.881 0.010 -0.016 0.009

V BV 23.706 0.011 0.065 0.013

V VR 23.705 0.012 0.103 0.027

R VR 23.492 0.007 -0.019 0.020

I RI 22.622 0.007 -0.107 0.021

u  ug 22.679  0.048  0.078 0.022

g  gr 24.602  0.045  0.057 0.020

r  gr 24.382  0.037  0.089 0.005

r  ri 24.400  0.037  0.089 0.023

i  ri 24.104  0.056  0.061 0.008

z  iz 23.481  0.025 0.160 0.090

Example of .kext file

Sections are identified by keyword site indicated in *.instr


UBVRI: 0.58,0.29,0.16,0.12,0.08

ugriz: 0.59,0.24,0.15,0.11,0.14

Example of SN coordinate file (name as you wish)

Objects to be fitted are selected when they occur in the selected field

sn1 11:18:53.156 +13:05:05.17 11:18:53.2 +13:05:15.17

sn2 11:19:00.156 +13:05:05.17

sn3 20:00:00.123 -50:00:00.20