Charter of the KOINet working group (pdf version)
There is no doubt that Kepler is the most successful
planet-hunting telescope in history. However, due to malfunctions
the observations of the Kepler field came recently to an
end. Therefore, the fate of many planetary systems that could have
been confirmed and characterized via transit timing variations (TTVs)
became uncertain. Since there are no forthcoming missions similar to
the Kepler space telescope in the near future, it is important to
arrange ground-based observations now, with the main goal of
continuing Kepler's heritage. This has been captured in the framework
of a multi-site and multi-institutional network called KOINet. The
present document is intended to show and make clear, right from the
start, the basic operating principles of the network. It is our
intention to minimize any misunderstandings that could appear during
the operation of the network, with the main goal to focus our efforts
in the production of scientific data and results.
Goal and main tasks of the KOINet working group
The main goal of the network is to characterize extrasolar
Kepler's planet candidates by means of the transit timing variation
technique. Other goals include observing Kepler eclipsing binaries,
and targets from the K2 mission. Further uses of this global
telescopes network can always be discussed and implemented within our
group. To reach our goals the working group members are expected to
contribute with the following basic tasks:
- To follow-up photometrically the primary transit events of the
pre-selected Kepler Objects of Interest (KOIs) in a
"homogeneous" way (see Appendix I for further details).
- To complete every observed night an observing log
as will be specified in Appendix I.
- To write proposals, when required.
- To plan individually the observing routine of robotic
- To analyze the photometric data to study and characterize the
Basic communication of the group
To facilitate the communication within the group, a mailing list has
been created. The mailing list can be found under the following link:
It is the duty of every participant to join the
mailing list. A potential participant will not be considered
as one until he/she has not been properly subscribed to
it. Subscriptions should be done using a full name and
an institutional email. The acceptance into the
mailing list is done by an administrator. Therefore, to be
accepted can take up to 3 working days. All emails that will
circulate within the mailing list are confidential
since it will contain information that will be discussed
within the group. Please, don't share it to anyone outside
Working group teleconferences will start on April and will be every 4
weeks during observations (March to November) and every 3 weeks once
the observations are already collected, when we can focus in the
analysis of the data. The telecons will be carried out at 6pm GMT and
will last about 1 hour. The dial-in information and agenda will be
distributed before the telecon and a resume will be distributed after
it. To arrange the agenda and take notes, one person from the network
will be selected. Everyone is invited to take part in the telecons. If
telecons are not required, an email will be sent.
Other information will be shared via a dedicated web page including
all necessary information to carry out the observations as efficiently
as possible, along with new light curves, target lists, transit time
predictions, data analysis and resultant papers, among others. All
this information can be found under the following link:
Once an observer has signed in to the group, he/she will be
provided with the unique user and password to access to the
"News" link in the web page, where the photometric data can,
by instance, be uploaded. Therefore, it is the duty of every
member of the KOINet to plan and prioritize their
observations with respect to the network's performance as a
whole, as discussed in the telecons, emails and web page.
Promotional allowance of KOINet
Until a first publication is out, allowance for KOINet's researchers
to present posters, give talks, and write talk/poster proceedings
about KOINet has been given. The basic rules are the following:
- Under the News section a web page is being build.
The page will contain plots such as acquired primary
transit light curves and O-C diagrams that researchers within the
collaboration can use to promote our collaborative work.
- Each plot will count with useful information such as the basics
on data reduction, detrending, and fitting.
- Following the spirit of the charter, as authors of the presented
talk should be listed the researchers who are
presenting the poster/proceeding/talk, the KOINet researchers involved
with the telescope that acquired the data that will be used in the promotion,
and the PI. At the end of the author list it should be stated
" ... and the KOINet collaboration".
- The PI should check the content of what is going to be presented at
least 4 days before the presentation date.
-Posters, proceedings, and talks (only dates and conferences) will be
collected and will be available to the community as advertisement of KOINet.
- Once the network is operational, a paper will be produced
presenting the network and showing first results. All of
the KOINet members at that time will be co-authors to that
paper. The initial paper will be led by the PI and the
Göttingen group and the remaining participants will be
- From then on, only if an observatory acquires data from the
KOI that is being under study, then the participants
involved with that observatory will be included in the paper
by default. Participants whose observations of a given object
failed (technical problems, weather, etc.) will also be
included in the mentioned publication if they can
demonstrate a serious effort to obtain their data. This is
intended to motivate and value the observers work. However,
to be fair to the rest of the group the observers will have
to show proofs of bad weather conditions (for example,
pictures of the sky, either from a satellite or an
observatory monitor) with clear dates and times on
them. Other ways this will not be considered. This, in turn,
is not valid for robotic telescopes. Staff at a given
observatory where time has been granted via a regular
proposal is not considered as observer. Only members of the
KOI network that have direct access to the telescopes do.
- The first-authorship of the publications will be,
generally, given to the members of the network that will
carry out the data analysis. Then, the remaining order of the
observers will depend of a compromise between the amount of
data and their quality acquired with respect to that
- If you agree to be part of the network, then you agree that
the publication of the observations from KOINets targets must
be coordinated within the collaboration.
- All light curves published by KOINet shall be made
available on, for example, the Exoplanet Transit Database
In order to promote the work and focus our valuable time into
science-related topics, the KOINet group will have the following
- Initially, the hosting institute of the project is the
Institute fuer Astrophysik Göttingen.
- Chair: the role of the chair is to serve as point of contact
for the working group, to organize telecons, to do the agenda, to
be the mailing-list administrator, and to organize other relevant
issues. It will start with the PI of the KOINet and will be
changed every 2 years.
- Board: KOINet's board will provide scientific guidance and
oversee the observations and analysis of the data. The Board
will also decide on any issue that is related to conflicts
between members. Initially the Board will be conformed by
C. von Essen, A. Ofir, S. Dreizler, H. Deeg and
- We expect the KOINet to grow. As the point-of-contact, the
PI is allowed to reject applications that are not deemed
compelling. However, membership will be decided by the
Board. A member can only be part of the network if he/she is
providing with considerable telescope time or shows proof of
TTV analysis skills. He/she will have the right to be part
of one telecon where an explanation of his/her contribution
to the network can be produced. A normal vote will be
produced. Any unclear result (by instance, an even yes and no
decision for membership) will be defined by the chair.
- The uncoordinated publication of data acquired within the
framework of this network may lead to expulsion from KOINet,
following a decision by its board.
Appendix I: Observing details
- The observations will be graded with respect to their
completeness and correctness. The grades will be 1 for complete and
correct observations and 0.5 for incomplete or incorrect ones. This
grading will be considered in the publication stage.
- Calibration frames should be acquired according to the
filter and binning configurations of choice (skyflats, bias
and dark frames).
- Science images should be acquired using a Johnson-Cousins R
filter or similar. I-filters are discouraged. If the filter
is not standard, then the observatory has to provide the
transmission function of the filter.
- Observers are free to take any other required step to
produce good quality photometric data (defocusing, guiding, windowing,
etc.), in compromise with a Kepler-competitive cadence (not more than
5 minutes per exposure, readout time included).
- Once the images are acquired, a night report has to be send to Göttingen
via the following web-page:
Please add there all relevant information such as changes in
the atmospheric transparency, in the cloud cov- erage, the phase of
the Moon, how close the Moon was to the target, any problem with the
CCD associated, by instance, to the cooling system, etc.
To improve the predictions as time passes by, it is very
important to send the data as soon as possible. Observations
without at least 7 bias frames, 7 dark frames which exposure
time should be the maximum exposure time of the science
frames (only if the observer knows that dark current is a
predominant noise source), 7 skyflat frames acquired in
filter Jonson-Cousins R, and the science frames acquired in
the same filter, binning and windowing configuration, are
not encouraged and will be badly graded. Bias frames are
encouraged to be acquired before and after the
observations. Due to potential changes in the weather
conditions flats can be acquired either at the beginning or
the end of the observing run, but before and after is
preferred. Skyflat counts have to be around 1/3 and 1/2 times
the dynamic range of the CCD. If weather conditions are too
poor to acquire skyflats during the observing run, flats from
previous nights are also acceptable (+/- 1 week). Domeflats
can also be acquired, specially under poor weather
conditions. However, skyflats are preferable.
- The keywords DATE-OBS with YYYY-MM-DDThh:mm:ss of the
middle of the exposure in UT, the exposure time, the right
ascension and declination of the target star, the gain in
e-/ADU, and the readout noise in e-, are strictly
required. If the observer does not have them available
then he/she should add them via the data acquisition code
options. If this is not possible, then a comment has to be added
in the night report under "Others", specifying the keywords setup.
- Any observation that falls in a proposed transit window
(see the "Events" link in the KOINet web page) counts as an
observation, whether the transit is observed or not. This is
motivated due to the fact that non-detection is also useful
to improve the TTV predictions.
- In the KOINet web page the most adequate reference stars
will be indicated (see "Catalog" for details). The observer
is excused to use the indicated reference stars only if the
field of view does not allows it. If this is not the case and
the observer does not respect the indicated reference stars,
then the observations will be badly graded.
- To ensure homogeneous light curves, the final data reduction will
take place in Göttingen. Therefore, the observer has to submit raw
data only. Data submission is under development (20.04.2014).