=================================================================
Michael's talk
1. Area to peak ratio from air-shower calibrated signals has been
investigated for a period  of more than 10 years as a function of the
station signals. The analysis has been done for several zenith angle
intervals from about 58 to 75 degrees. The A/P shows an increase over
time for low zenith and a decrease for larger angles with a switch at
around 65 degrees. The effect is not very worrisom (about 1% in this
variable) for the neutrino analysis. The analysis will be extended to
lower angles.

Koun: Which is the purpose of this analysis?
Michael: This variable is used in the neutrino searches which is  now
extended to lower angles. For the old analysis this effect did not
matter, the check was done to the new angles.

Ioana: Which is the em/muonic ratio on station signals for these angles?
Michael: Not sure, but studies should be found in the thesis of Louis
(and Ines n.a.). Speaking with Eric they think that one possible
explanation for this is that the liner degrades on the bottom (?). The
em/mu ratio should not change over time.
Ioana: The em/muonic ratio from air-showers should not change indeed,
but the measured em/muonic ratio can change if the tank has a localised
degraded reflectivity due to the different location of the produced
Cherenkov photons for the two components.

====================================================================
Koun's talk on the ICRC content
2. Koun presented plausible plots for the content of the ICRC. The
discussion on each plots was quite detailed with contributions to the
discussion from Lorenzo, Francesco, Jose, Ralph, Corinne, Ricardo (who
else?). I summarize here  just the decisions.

FD/Hybrid
===
1. Event rate should be shown (general agreement) for simple
reconstruction cuts for individual eyes.
2. Event rates with Xmax quality cuts => not clear. Decision to be taken
after seeing the plots. The worry (from Jose) is that data from LA were
not used for one year due to the EBS clock problem. General agreement,
here is no reason not to show this, if a small sentence is written in
the text.
3. FD ontime preferred over the efficiency plot and should be shown. The
shown efficiency is relative to the time that the HV is on, maybe not
the best reference.
4. EFD/S38 plot is too complicated and not sufficiently understood, so
it will not be included (general agreement). A discussion restarted on
this plot:

Ralph: Is it corrected the drift in the energy in data and then computed
the systematic?
Lorenzo: No

Ralph: What causes this drift and the jump? We should organize a meeting
just related to this plot.
Lorenzo/Francesco: Phong has shown that it is related to the cleaning of
the filters. If it is the filter then it is not included in CalA.

5. A plot showing the mean Xmax as a function of time, or just in two
time intervals (Ralph). To be decided after the plots are produced.

6. A plot to show the long term performance of the other instrumental
parts of our Observatory, lasers, calibration, etc. Francesco is in
contact with Gaetano for this and will come back to the list with more
info. Input has been also asked to Laura by Ioana.

SD performance
===
1. Event rates for 750/1500 m arrays to be included
2. A/P profile and curent status of the decrease and the future prediction
3. Data quality performance plot => we still need some input on this.
Maybe the attenuation parameters as a function of time, or a plot on the
air-showers A/P as produced by Michael (?)
4. Ontime of the SD ( see also email from Corinne)
5. Battery lifetime performances. Ricardo is saying that this is quite
complicated study, that cannot be done very fast. Ioana: this would be
interesting maybe to try to automize also as a general interesting
information for the task.

General: The abstract will be re-written to include more details.
Data period: For the data that needs analysis: 12/2017 (needs DBs).
Ontime and some other plots can be produced with data period until ICRC.

===========================
News from Malargue
===========================
Jonny informed us that the HEAT hydraulic system replacement parts have
arrived in Malargue. When Primo and Leandro are back from holidays they
will be installed. Also a change of the oil is foreseen.
Mariano: Even with this problem, HEAT is taking data, with all the
telescopes in the upwards position.

Ricardo/Mariano=> nothing special happening, shifts going smooth (with
the standard issues that are solved fast). There will be a shift report
including the volcano ashes influence.

Ioana (from information of Juan Pablo): Alexis and Observatory staff
started opening the PMTs from the PMT week and a report on corrosion
will be done next meeting (?)

===================================================================
Next meeting will be in 2 weeks: 31st of January. Discussion and
comments are encouraged meanwhile on the list.