AndiB_LabJournal.txt

Day1 (4/1)
Write-up deadline is June 7th (last day of class)
	can use ARCSAT, MAST, SDSS... generally optical
	(should I do things with MRO, solar telescope, radio???)
Shells are variants on unix that set behaviors on how you interact with it. default is bash.
	(ubuntu failed me so I'm going to replace my operating system eventually)
	(do ls -a to see invisible files)
Navigate unix with overthewire.org/wargames/bandit

Day2 (4/3)
A fork is a separate cloned copy of the repository that i can work on separately without affecting the main tree
a branch is within the main tree but doesnt touch all of the files?
a remote is a pointer for the fork; a local boy is the thing that you have to commit and push to a designated remote.
saved list of collaboration git commands at https://education.github.com/git-cheat-sheet-education.pdf

Day3 (4/5)
Got assigned Lick Observatory, window of observation starting april 1st and ending april 15th
Spent a lot of time searching through different catalogues of quasars until we found one visible from the northern hemisphere
Spent the rest of the time formating different timezone readouts, making sure the local time was different from UTC which is different from arizona time

Day4 (4/8)
Got another partner who did research on quasars and had a catalogue containing much fewer quasars than had been downloaded from SDSS
turned the data into a panda table, learned how to rearrange/rename/delete columns, and finished up the activity for apache point
learned how to set the origin for my remote, got yelled at for using sudo

Day5 (4/10)
spent downloading astroplan and becoming familiar with target lists
didnt know there was a function for constraining the targets based on ra and dec and spent a substantial amount of time drawing the galactic coordinate system

Day6 (4/12)
created a mask of the panda data frame that only contains targets viewable at night
converted coordinates to hr angle and degree using skycoords
input the window start/end times, converted to an interval occurring at astr twilight
constrains contained moon illumination
created a table using observability_table(constrains, lick, targets, time_range=observing_range)
ran into an error where the constrains arent recognized. almost done with this, will submit code tomorrow after volunteering at astroball =)

Day7 (4/15)
freedom w data used for the final paper but PROBS just 1 day of ARCSAT
with reading scientific papers (for the purposes of obtaining references):
-read abstract/conc n look at plots first
-search via keywords
-use ags to see if the paper is one in a series
-summarize what you read immediately after reading, and include bibtec info alongside, store in an accessible place
ideas:
-cepheid variable... cant compare across wavelengths
-constraints on observation is what should be focused on. dealing with data, dealing with noise
-delta scuti ? on the instability strip, timescale of pulsation is only a few hours
-astroseismology?? looking for pulsational modes using kepler r-tests, short timeseries of bright stars, talk to merideth rawls (?)
-deblending/centroiding to find binaries, depending on resolution

Day8 (4/17)
-using astropy isnt great for fits files but theres a thing where you open with .fits, set a variable for the header, then open info using repr(file_header[0])
-for project: giving up on brett's strange dynamic star
-observe variable stars include delta scuti, Rapidly oscillating Ap stars, alpha cygni variables
-delta scuti are low mass (A0-F5), high metallicity, period of .5-7hrs. amplitudes larger than .3mag are HADS or dwarf Cepheids
-roAp have short-timescale variations ranging from 5-23 min. high-overtone, low-degree, non-radial pressure modes. axis of pulsation aligned with magnetic axis, modulating the amplitude
-Alpha cygni variables have longer variations (days to weeks), irregular pulsations w amp .1mag, non-radial pulsations. supergiant (B or A). blah. long period. blah.

Day9 (4/19)
-we observe apparent mag, not absolute mag
-CCDs interpret photons which interact with the material, exciting an electron which can fall into a potential well
-instrument then registers that well as a 1
-oversaturation results in overflow of electrons into the wells above and below
-Resolution = wavelength / diameter of aperture
-spectroscopy is flux per unit wavelength
-airmass, dust gets in the way
-turned in proposal!!!! i can do both types of variable stars!!!!

Day10 (4/22)
-i was a gross sicko, didn't attend class in order to not infect people

Day11 (4/24)
-used the metal pirate-spectrograph to see how slit size affected resolution of spectral lines
-plastic blue spectrograph could distinguish wavelength of spectral lines
-i looked at a lot of lamps (helium, nitrogen, deuterium) and then me zach n prof tuttle talked about adhd while i had pasta

Day12 (4/26)
-skipped to do 226 hw, told that the class is optional
-made a list of roAP stars with periods less than ten min

Day13 (4/29)
-introduced to the CCD lab.... Anika, Megan, two others are my partners
-downloaded the uw VPN
-travel to apo website and click on multiple weather forecast for IR, cloud movement (atmospheric seeing which broadens spatial resolution)
-want mirror to be the same temp as the air... wind affects dome closure
-"current weather summary" gives a dark screen describing all telescopes on mountain. yellow/red text denotes alarming conditions
-rec: use a finding chart of the sky with digitized sky survey

Day14 (5/1)
-CCD lab time! We went into the TEG AUEG corner to the spectrograph, which will eventually be underneath MRO (I'll be in charge of programming an arduino to turn the spectrometer lamp on/off)
-a pencil was used to prop open the box which the CCD was pointed into. lamp could be turned on/off, illuminating the slit
-usb plugged in, camera connected to CCDsoft, temperature turned on which turns on the fan. both imager and autofocus turned on
-i played with the exposure, bin size, light, etc. while we set up the format
-for flats, an exposure time of 90 seconds was sufficient for a solid circle and max saturation of 48,000 counts
-reduced exposure by 9s until 18s. saved all fits files to my usb which i emailed to my groupmates

Observing (5/2)
-VPN client didn't work on my tablet, so I used my windows computer to login. took a while to get things moving.
-took bias. couldn't determine how to take flats without it being twilight... couldve made dome flats, but that wouldve required us to close the dome
-first exposure i tried to take, i checked the autofocus boxes, which the system really didn't like. it took a while to bring the observatory back online
-after some trial and error (i had very optimistic limits for RA), i was able to take images of four different roAp stars!!!!!!
-the first two i imaged were more test-run-y... the last two had periods of 5.4 and 8.3, and i used halpha and sdss_u for both
-couldnt figure out how to download the files so i'll do it in class tomorrow!!!!

Day15 (5/3)
-determined how to fts the files... basically. i didn't need permission, and didnt need a vpn yesterday. went to localhost in my terminal, cd'ed into my specific directory
-mget the fits files! megan took flats but they werent in bin4 which is brutal. i'll probably have to retake all my observations, which is fin
-opened the files... the halpha exposure of HD 137949 is just. empty. which is super weird. i'll be able to try other filters later
-i think i'm going to stick with two of the stars, HD 137949 and HD 134214

Day16 (5/6)
-reasserted deadlines - CCD lab due next monday
-things we want to know about our CCD's:
"full well": max electrons a pixel can hold... bigger pixels (bins) can hold more charge. measured using a photon transfer curve
"read noise": false positives... measured by calculating the standard deviation of bias
"charge transfer efficiency": transferring loss from pixel to pixel, usually super efficient. use Fe55 x-ray source then do stats of how much transferred
"dark current": caused by thermal charge generation, reduced with cooling. measured with taking darks.
"quantum efficiency": how efficiently the ccd detects light. measured with standard, well-calibrated illumination. often variable with time/wavelength.
-photon transfer curve lets us know which portion of the CCD gives a linear behavior. a full well has a slope=1
-shot noise is the time for photons to hit even if coming from the same source.
-ADC is the electronic component that performs the conversion from analog to digital... it has a defined number of bits which dictates max output. if the ADC has 16 bits, max value = 65500
NOISE:
-usually read noise (bias) or shot noise (bright) regime. signal to noise is either ~S (read) or ~sqrt(S) (shot)
-alter ADU saturation when using up a byte by having both positive and negative bias (if u set all bias to zero straightaway). bias is not a function of time.
-flats reveal pixel to pixel variation. histogramming creates a gaussian distr. we flatten our observations by dividing by the flat fields
DARKS:
-scales with time
-can show large scale pattern noise (like if there are mechanical cooling boys that aren't constant across the CCD)

Day17 (5/8)
-fixed astroplan!! scheduled an observing run
-was late to class bc my grandpa died and i had family stuff messing up my day

Day18 (5/10)
-lots of reasons that you may not pick the center of your object (avoid bright object)
-dots in the vingetting (part blocked by the instrument) and main image are cosmic rays. are not gaussian, maybe more streaky, while stars are round
-infrared sky glows, including in spectral data. very difficult to calibrate in the infrared