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====== Redshift realease I: ======

Dear all,

I've just finished measuring the redshifts for all the targeted galaxies in A2192. The remaining ones (those of A963) are soon to come! 

In the table below, you will find:

> A total of 434 galaxies placed in fibers (100%)  --- Unique galaxies are 377 (because 50/434 were observed more than once - 7 galaxies 3 times and 43 galxies twice)
> z's are measured for 314 galaxies (72%) -- Note that I put z=99.99 when I coudn't get anything
> good (trustable) z's for 232 galaxies (53%) -- There is a column called "trust" for which I've put 1=trust this z; -1=not very secure but ok-ish; -2: not secure at all
> 51 redshifts available from the literature to compare with our redshift measurements (12%) -- I include HI redshifts in "literature"

The table columns are:
  - Galaxy ID (running number of the detection as reported by sextractor)
  - AF2 Configuration (for my own tracking, b1 means bright1, and so on)
  - Fiber Number (also for my own tracking)
  - zmio = My redshift measurement
  - trust = 1 if its a good reshift, -1 if its not 100% secure and -2 if its doubtful
  - zlit = literature redshift
  - zf = zlit source. For A2192 the numbers are: 1 = WSRT HI redshift; 2 = SDSS optical redshift; 3 = WIYN; 4 = WSRT&SDSS; 5= WSRT+WIYN
  - RA (from photo-tables)
  - DEC (from photo-tables)
  - B mag (from photo-tables)
  - R mag (from photo-tables)

**Notes of caution:**

**I.** From this table you might notice that if you compare my redshifts with those of the literature, there is good agreement, ALTHOUGHT, there are 3 (/51) galaxies that have quite different redshifts. We are now investigating what is the source of the problem here, we guess that its probably a matching problem between the coordinates of our targets and those in some of the literature.... 

**II.** When doing the morphology classification, Bianca identified quite a few postage stamps where there was supposed to be a galaxy and instead there was nothing more than the spike of a nearby star. Unfortunatelly, we think some of these "objects" got through the spectroscopic target selection and hence we expect to have a percentage of redshifts=-99.99 (which we indeed have). We still need to cross-correlate the no-redshift galaxies with the no-morphology galaxies to see if they are really the same group of objects. (a preliminary morph analysis comming soon)

**III.** This table is not unique, there are 50 galaxies that were observed more than once! Unique table comming up soon!

{{budhies:optical:wht_spectroscopy:A2192_zs_v2.table.tar.gz|The redshift table for A2192}}

For those that just want a quick view of the redshift distrubution (of A2192), I attach a (quick & dirty) plot below. The blue bars are our redshifts and the green are those available from the literature. I only used secure redshifts for this plot!

{{budhies:optical:wht_spectroscopy:A2192_z_hist.png?300}}

====== Redshift release II ======

Below, you can find the unique redshift table for A2192 (By unique I mean only 1 redshift per galaxy). 

In general the multiple measurements were consistent. I took the average when all the trust flags were the same, or the most trusted measurement elsewhere. There was only one case for which the redshifts did not match, this was for galaxy 94683, where I got z1=0.14277 and z2=0.35081. I went back to the spectra and found the same redhifts, but slightly less certainly in the second, hence, I quoted z1 with trust=-2 to be very conservative!

Total No. unique galaxies in A2192 = 377


{{budhies:optical:wht_spectroscopy:A2192_zs.unique.table.tar.gz|The UNIQUE redshift table for A2192}}

====== Redshift release III ======

For those of you intending to use the redshift table, please remember that when we targeted the galaxies for spectroscopy, we tried not to use too many fibers for galaxies for which we already knew the redshifts (from the literature). 

In total there were 93 galaxies with redshifts from the literature and 49 of them were observed again in the spectroscopic runs (also to have an estimate of how good our zs are). Hence, there are 44 galaxies with literature redshifts that ARE NOT in A2192_zs.unique.table

I copy a table with these galaxies, their redshifts and some other photometric information here:

{{budhies:optical:wht_spectroscopy:A2192_zlit_that_were_not_targ_in_spec.txt.tar.gz|Additional z-table (from the literature) for A2192}}

Additionally, I've prepared a big table that contains all redshifts (mine when availabe, and literature when mine not available). This table is called A2192_all_zs.table and you can downloaded from the link below:

{{budhies:optical:wht_spectroscopy:A2192_all_zs.table.tar.gz}}

The columns of this table are:

  -  ID of galaxy
  -  z (my redshift when available or zlit otherwise)
  -  trust (as before, and trust=2 when the redshift is from the literature)
  -  zf = redshift source (as before)
  -  RA
  -  DEC
  -  B mag
  -  R mag


Note: there were further WIYN and SDSS redshifts available but these redshifts were outside the range targeted by the HI observations and hence not in these tables but I will track them down to see if they are useful...

====== Redshift release VI ======

The redshift table for **Abell 963** can be found here:

{{budhies:optical:wht_spectroscopy:2all_A963_z.table.tar.gz}}

In total this table has 492 redshifts, but note that 30 galaxies in this cluster were observed more than twice and hence the table above is not "unique". The total number of unique galaxies (with WHT spectroscopic redshifts) is 459!

For a unique version of the z-table please download the following file:

{{budhies:optical:wht_spectroscopy:2all_A963_z.unique.table.tar.gz}}


(The table columns are written in the 1st line of each table)

And finally, just below you can also find a quick view of the redshift histogram for this supercluster:

{{budhies:optical:wht_spectroscopy:A963_z_hist.png?400}}


====== FINAL REDSHIFTS ======

I've created final z-tables for the 2 clusters. the tables contain my redshifts plus literature redshifts inside and outside the z-range targeted by the HI-observations (you can identify them with the 2nd column).

The table columns are: 
  - ID
  - Configuration (name of AF2 configuration if observed at WHT, "none" if it was not observed but it has literature reshift in the z-range of thwe HI observations and "non_targ" if the literature redshift is outside the HI-range and was hence not even targeted)
  - Redshift: I quote my redshift when available, if there was also a literature redshit, I put it only if my redshift was unsecure,  =99.99, or not available)
  - trust: the reliability of the measurement: 1=secure, negative=not so secure, 2=from the literature
  - zf: source of redshift (as before)
  - RA
  - DEC
  - B-mag
  - R-mag

And the tables can be downloaded here: 

{{budhies:optical:wht_spectroscopy:the_2_final_z_tables.tar.gz}}

And the final view of the z-histograms is:


**A963:** 

{{budhies:optical:wht_spectroscopy:A963_zal_hist.png?600}}

**A2192:** 

{{budhies:optical:wht_spectroscopy:A2192_all_zs_hist.png?600}}

Note1: Redshifts of all trusts were considered for the histograms, although I would reccomend the use of redshifts with trust > 0 in general.

Note2: Two galaxies had SDSS redshift and HI redshift that did not agree. These Galaxies are 84982 and 22082 (in A2192 and A963 respectivelly). In the image, the galaxy 84982 seems to be a foreground optical counterpart of the perhaps further away HI blob. The HI detection is not too save anyway (Marc told me) so I kept the SDSS redshift in the table. For 22082 I also wrote the SDSS z value (=0.02481), because it seems its a similar situation.

====== On the completeness & success rate======

**__For A963__**, 925 galaxies were targeted. But after doing the morphology classification, we found that some galaxies were not real galaxies, but actually image defects or star spikes that were being identified as obkects. If we take this out from the targeted galaxies, we are left with **848 targeted galaxies**. From those, **437 were observed with AF2/WHT**.
 From the observed galaxies, we got **306 redshifts** and **201 secure redshifts
**

NOTE: When doing this check, I spotted some redshifts that corresponded to this defect-galaxies that should not have been targeted. This redshifts are for sure wrong and are probably related to light coming from some other source nearby. these are: 48148, 50817, 68325. please be aware of them when you use the final tables. The easiest is to change their trust to -2!

Here are a couple of complementary plots:

{{budhies:optical:wht_spectroscopy:A963completeness.png?400}} {{budhies:optical:wht_spectroscopy:A963completenessB.png?400}}

**__For A2192__**, **563 galaxies were targeted** (I've already excluded the defect-detections here), **339 of those were observed** (we lost  38 fibers in galaxies that were not really galaxies due to the abovementioned problem). We measured **redshifts for 266** of them and we measured **good redshifts for 205**.


{{budhies:optical:wht_spectroscopy:A2192completenessR.png?400}}