A great analogy to explain the LFC

Richard's written a piece that neatly explains what makes the comb such a powerful wavelength calibration tool...  Read all about it here!

Even the stray light from the comb's spectacular!

Night Log 2016-04-29

SA: Petri
SO: Fred
Others: Lisa, and small tel observers etc for LFC tour

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After an active day with the media and visitors, the night was quiet.
Could not open due to rain, cloud, wind. Sub-zero temperatures.
But looks much better for tomorrow.

Night Log 2016-04-28

SA: Petri
SO: Fred
Others: Lisa, Ted, Ramotholo, Eric, Derryck, Richard

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Night started out fine with several hours of one arcsec seeing once
again, but had to close due to humidity before 11pm already.

Before closing, took science for:

2015-2-MLT-006 P1 RSS (Characterising Strong Gravitational Lensing systems)
2015-2-SCI-023 P2 HRS (HRS spectroscopy of eclipsing stars in Omega Centauri)
2015-2-SCI-031 P2 RSS (Connecting QSO absorption line systems with the associated galaxies)
2015-2-SCI-029 P3 RSS (x2) (Spectroscopy of Kepler K2 White Dwarfs)

So how do these LFC things work?

Derryck gave Tech Ops a great introduction to LFCs on Monday morning, here are a couple of slides from his presentation...

First of all - some laser basics

Then the parameters that define a LFC

& how those properties are established

The 4 primary components of the comb are shown in the pic below: the titanium sapphire laser (1), a diode laser stabilised to a rubidium transition (2), a photonic crystal fibre for super-continuum generation (3) & a Fabry-Perot filter cavity (4).

The main components of the LFC on the optical bench

So at the heart of the system is a titanium-sapphire femtosecond pulsed laser.  The Ti:sapphire crystal glows red/orange when excited by the laser light & the copper block that holds it needs to be water-cooled while the laser is running.  This main (Ti:sapphire) laser is pumped by a frequency-doubled, continuous wave, neodymium-doped yttrium orthovanadate (Nd:YVO4) laser that's powered at 6 W.  Frequency doubling of the Nd:YVO4 converts the invisible infrared light (at 1064 nm) to the characteristic green light at 532 nm that's needed to produce the red (800 nm) Ti:sapphire beam.  The ~30 cm round-trip path length of the Ti:sapphire laser cavity sets the repetition frequency (mode spacing of the comb) to just less than 1 GHz.  That 1.2 W beam is what's needed to make all the cool stuff happen, but there's quite a bit to be done to the light before we can fire it into our spectrograph.

A glimpse inside the Ti:sapphire laser, being pumped by a powerful Nd:YVO4 laser

There's a third laser in the system - a continuous wave diode laser that produces a ~40 mW beam of red light (around 780 nm).  This passes through a rubidium gas cell & one of the resulting transitions (which are superbly traceable atomic references) is then used to lock the Ti:sapphire modes.  The extremely well established wavelength of that line (780.24629 nm) also serves as a definitive reference point for our wavelength solution.  By measuring its exact position in our HRS spectra (to a minuscule fraction of a pixel), & then being able to count the comb teeth (whose separations in frequency space are exactly known due to the locked repetition frequency of the comb) will allow us to accurately map where each spectral feature is located in wavelength space.  This is The Holy Grail of wavelength calibration, which is absolutely critical for high resolution spectroscopy, & particularly for the precision radial velocity measurements needed to detect low mass exoplanets.  Of course all of this calibration work is Much easier said than done - but that's the principle anyway!

Power supply & controls for the diode laser that produces the rubidium line used to lock the comb spacing & establish the wavelength scale for the comb (& hence for the red arm of HRS!)

The next critical component on the LFC's optical bench is the 50 cm long loop of photonic crystal fibre (PCF).  The core of this fibre is only about 3 microns in diameter so the rubidium & Ti:sapphire beams need to be carefully steered & aligned in order to couple them properly into the fibre input (the reddish spot to the right of centre in the pic below).

Coupling the 2 laser beams into the photonic crystal fibre's input face

The cladding of the PCF has an elaborate micro-structure with air holes.  The holes reduce the effective refractive index of the cladding, which then improves the confinement of the modes & thus increases the intensity of the light within the fibre.  This high intensity is necessary to drive the non-linear process required to broaden the spectral range of the comb & to produce what's known as the super-continuum.  One can literally see the colour of the light change as it traverses the length of this extraordinary little fibre!

The photonic crystal fibre that broadens the spectral range of the comb by roughly a factor of ten

What looks like a continuous spectrum (similar to what one gets out of a spectrograph when you inject white light into it) is in fact made up of countless individual laser wavelengths - it's a rainbow of closely spaced laser spots!  It's these spots that have immaculately defined wavelengths that can be used to precisely calibrate our high resolution spectroscopic data.

The spectacularly beautiful super-continuum produced by the LFC

Making minute adjustments to the X/Y position of the fibre input using fine micrometers on the stage assembly changes the colour of the light emerging from the fibre exit!  While this may seem reasonable to a laser physicist, for most of us this is best explained by invoking the existence of pure magic...

Note the yellow & red spots on the hand, these are from the fibre output & the original Ti:sapphire beams

A tiny tweak of the fibre input turns the green beam from yellow, to orange, to red.  The profound novelty remains, even after a week of playing with this!

Minutely adjusting the fibre alignment varies the width of the super-continuum that's generated, changing the colour of the light emerging from the PCF

The last "sub-system" on the optical bench is the Fabry-Perot cavity.  This device is basically a tunable filter that's used to knock out all but every 15th line, so that the comb's not too dense to be useful.  A pair of partially reflective plane-parallel mirrors with complementary coatings are mounted on piezo-electric actuators that allow the spacing of the mirrors to be tightly controlled.  The mirrors first need to be optimally aligned using the precision micrometers that control the tip & tilt of the smaller mirror with respect to the larger, fixed one.  The light bounces between the two mirrors & constructive interference leads to certain wavelength ranges being preserved (transmitted) & others being eliminated through destructive interference.  

The Fabry-Perot cavity used to filter the super-continuum: the small mirror to the right of the centre of the image gets aligned in tip/tilt wrt the larger one on the right, & then the mirror separation is controlled with piezo-electric actuators until the required wavelength range is transmitted

It's this filtered version of the comb that then gets directed to the injection fibre (the blue cable visible near the back of the bench in the pic below).  That fibre is used to convey the comb light to the HRS high stability bench, where it gets introduced into the spectrograph in much the same way as the ThAr lamp light that's conventionally used for HRS wavelength calibration.

Aligned & locked LFC - with the lights on in the room

Each of these units need to be locked to preserve the comb.  The Ti:sapphire laser is mode-locked, & then there are 3 electronic locks: the diode laser to the sharpest of the rubidium transitions, the repetition rate (the frequency that sets the spacing of the comb teeth) & then the Fabry-Perot cavity.  With all of these locked & stable, we have a LFC that's good to go!

The scene's even more spectacular when the room lights are switched off!

More tomorrow about injecting the comb light into HRS!

Night Log 2016-04-27

SA: Petri
SO: Fred
Others: Eric, Lisa, Richard, Derryck

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Great night. Excellent seeing, clear save some thin cirrus wisps, and
stable temperatures and low humidity all throughout. Did some fun
engineering observations on-sky (Jupiter's moons for example!) with
the Laser Frequency Comb, and a large number of good quality
science observations:

2015-2-SCI-028 P1 RSS (Confirmation and redshift determination of galaxy clusters)
2016-1-SCI-022 P1 RSS (Searching for high redshift quasars for the MeerKAT Absorption Line Survey (MALS))
2015-2-MLT-004 P1 RSS (Unraveling ring galaxies)
2015-2-SCI-028 P1,2,3 SCAM (x3) (Confirmation and redshift determination of galaxy clusters)
2015-2-COM-004 P2 HRS (x2) (Commissionning data for HRS)
2015-2-SCI-021 P2 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-SCI-023 P2 HRS (HRS spectroscopy of eclipsing stars in Omega Centauri)
2016-1-SCI-036 P3 HRS (Study of the evolution of massive stars in our Galaxy.)
2015-2-SCI-029 P3 RSS (Spectroscopy of Kepler K2 White Dwarfs)
2015-1-MLT-002 P3 RSS (Observations of supernovae, near and far.)
2015-2-SCI-001 P3 HRS (Gravitational redshifts in planetary nebulae and spectra of dwarf tidal galaxies)

Getting the LFC set up

The LFC's horrifically complicated looking optical bench was set up on its pneumatic isolators, atop a thoroughly unpretentious old office desk that was dragged into the HRS electronics room for the occasion.

Getting things back together again after the trip

Some careful cleaning of the optics was in order, to remove dust that had accumulated during the packing, shipping & unpacking processes.  A delicate task, expertly executed.

Cleaning dusty mirrors with alcohol & patience

The array of electronics associated with the comb, much of it custom-built, is a formidable sight as well...  Fortunately it's not usually necessary to directly access the HRS computers (visible in the background), instead we run the spectrograph from the SALT control room, or via a remote desktop connection.

Getting acquainted with the hardware

It's a good kind of chaos - really!

The HRS electronics room after its LFC make-over

& the comb's optical bench is truly a work of art!  The guys usually operate on a much larger optical table in their lab.  But for the sake of making the comb transportable, everything had to be crammed onto a breadboard that would fit on a standard pallet.  As a result, some of the beams require fairly creative steering to negotiate the tight confines of the perspex enclosure, while still having to check in at all the appropriate stations along the way...

Herding laser beams around!

Astronomers are forever scrounging for whatever light they can accumulate, so it's been bizarrely entertaining for us to operate in such a photon rich environment.  For example: to inject the comb light into the little bench-top spectrometer, & avoid saturation, one simply has to deflect part of the beam into the instrument with a piece of paper!  

Swatting light into a spectrometer

Part of the fun is trying to trace the various laser beams as they criss-cross the optical bench, bouncing off of & passing through a multitude of mirrors, beam-splitters, polarisers, lenses & irises, before entering different fibres & detectors (including fast photodiodes & even a mini spectrometer).

Even better than LEGO & Meccano

Tomorrow we'll get more into how the comb works & what all the many bits do...

A Laser Frequency Comb at SALT!

A week ago today we were joined at SALT by Derryck Reid (left) & Richard McCracken (right) from the Ultrafast Optics group at Heriot-Watt University in Edinburgh.  

Laser lads in action!

Their experimental laser frequency comb (LFC) had arrived in the country ahead of them & was safely transported up to Sutherland on 19 April.  The plan being to set up & couple the comb to SALT's High Resolution Spectrograph (HRS) for a 3 month field trial.

LFC safe & sound in Sutherland

This project's hugely exciting for all concerned!  SALT gets to work with & learn about a state-of-the-art calibration device that will allow us to exploit the HRS's full potential as a precision radial velocity instrument.  While the H-W team gets to test their lab instrument in a realistic operational environment, & obtain high quality astronomical data that will inform the refinement of frequency comb designs for astronomical applications.

Light & magic fills the HRS electronics room

It's also incredibly stimulating & productive for people from widely different scientific disciplines to get to interact intensively in pursuit of such complementary interests.  Given all that's happened in just a week, we're already all looking forward to what could unfold over the coming months & years!

Night Log 2016-04-26

SA: Encarni
SO: Veronica
Others: Petri, Ant, Lisa, Eric, Nic, Rudi, Derryck, Richard.

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Another clear night (well, with some thin cirrus) and very nice seeing! Unfortunately we had to stop observing at about 1:30am due to a technical problem.

Obtained awesome science data for:

2015-2-MLT-001 P0 RSS (Followup spectroscopy of transients)
2015-2-SCI-028 P1 RSS (Confirmation and redshift determination of galaxy clusters)
2016-1-SCI-022 P1 RSS (x3) (Searching for high redshift quasars for the MeerKAT Absorption Line Survey (MALS))
2015-1-MLT-002 P3 RSS (Observations of supernovae, near and far.)
2015-2-SCI-028 P3 SCAM (Confirmation and redshift determination of galaxy clusters)
2016-1-MLT-003 P3 RSS (x3) (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-25

SA: Encarni
SO: Veronica
Others: Eric, Rudi, Lisa, Nic, Derryck, Richard.

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First light for the Laser Frequency Combe on the HRS! Whoo hooo! :) Congrats team HRS-LFC! :)

Oh and Veronica and I casually broke the record for the number of science blocks in a single night, despite a late start due to high humidity and spending nearly 2.5 hours on engineering stuff... guys, the bar has been raised!

Just to brag a bit more, here are the lucky winners!

2016-1-SCI-038 P2 RSS (Spectra of all variable White Dwarfs observed in the Kelpler K2 survey)
2016-1-SCI-012 P2 RSS (x3) (Revealing evolved massive stars with Spitzer, WISE and SALT)
2016-1-SCI-025 P3 RSS (x8) (Spectral classification of rapidly pulsating stars)
2016-1-MLT-003 P3 RSS (x17) (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-24

SA: Encarni
SO: Veronica
Others: Lisa, Rudi, Richard, Derryck, Nic, Eric.

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At last, a beautiful clear night with mostly good seeing that lasted all night! :)

Science data for:

2016-1-SCI-038 P2 RSS (Spectra of all variable White Dwarfs observed in the Kelpler K2 survey)
2016-1-SCI-025 P2 RSS (x3) (Spectral classification of rapidly pulsating stars)
2015-1-MLT-004 P2 RSS (Deriving the mass of the black holes in the core of active galaxies @romeroencarni1 @sand_dave)
2016-1-MLT-002 P3 HRS (x3) (Analysis of metallicity gradient and local chemical composition heterogeneity in the Galactic disk)
2016-1-SCI-036 P3 HRS (x3) (Study of the evolution of massive stars in our Galaxy.)
2015-1-MLT-002 P3 RSS (Observations of supernovae, near and far.)
2016-1-MLT-003 P3 RSS (x2) (Spectroscopic observations of bright RR Lyrae variables)
2015-2-SCI-001 P3 HRS (x2) (Gravitational redshifts in planetary nebulae and spectra of dwarf tidal galaxies)
2015-2-SCI-055 P3 HRS (Probing winds from the center of the Milky Way (@astrocrawford))

Night Log 2016-04-23

SA: Encarni
SO: Veronica
Others: Ant, Blaise, Eric, Derrick, Richard, Nic, Rudi, Lisa. Ted remotely for FP.

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Finally! A truly beautiful night with clear skies and decent seeing - such a pleasure! At least it was until the relative humidity suddenly zoomed up at 4:30am and forced us to close. Sniff.

Science data for:

2015-1-MLT-002 P0 RSS (x3) (Observations of supernovae, near and far.)
2015-2-SVP-001 P1 RSS (RSS-FP R commissioning)
2015-2-SCI-019 P2 RSS (Searching for binaries in unusual central stars of planetary nebulae )
2016-1-SCI-005 P2 HRS (Spectra of dwarf and tidal dwarf galaxies)
2016-1-SCI-012 P2 RSS (Revealing evolved massive stars with Spitzer, WISE and SALT)
2016-1-SCI-036 P3 HRS (Study of the evolution of massive stars in our Galaxy.)
2015-2-SCI-055 P3 HRS (Probing winds from the center of the Milky Way (@astrocrawford))

Night Log 2016-04-22

SA: Encarni
SO: Veronica
Others: Lisa, Derrick, Nic, Eric, Richard, Ant.

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Stormy weather followed by very wet conditions. No science data taken tonight either.

Night Log 2016-04-21

SA: Encarni
SO: Veronica
Others: Blaise, Anthony, Lisa, Derrick, Richard, Eric.

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Another cloudy and humid night. Did some tests with the Fabry Perot system, but no science observations.

Night Log 2016-04-20

SA: Encarni
SO: Veronica
Others: Blaise, Anthony, Eric, Richard and Derrick, Fred.

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Humid and wet conditions tonight. No science observations taken.

Night Log 2016-04-19

SA: Marissa
SO: Thea
Others: Enrico, Encarni, Fred, Etienne

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Rained during the day but it cleared eventually, yielding decent seeing on this bright night.

Data taken for:

2016-1-SCI-025 P2 RSS (x4) (Spectral classification of rapidly pulsating stars)
2015-2-SCI-021 P2 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2016-1-SCI-012 P2 RSS (Revealing evolved massive stars with Spitzer, WISE and SALT)
2015-2-SCI-019 P2 RSS (Searching for binaries in unusual central stars of planetary nebulae )
2015-2-SCI-001 P3 HRS (Gravitational redshifts in planetary nebulae and spectra of dwarf tidal galaxies)
2016-1-MLT-002 P3 HRS (x7) (Analysis of metallicity gradient and local chemical composition heterogeneity in the Galactic disk)
2015-2-SCI-055 P3 HRS (Probing winds from the center of the Milky Way (@astrocrawford))

Night Log 2016-04-18

SA: Marissa
SO: Thea
Others: Enrico

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This bright night with some clear hours and some cloudy hours was used as best we could, thanks to the newly populated queue of ours.

Data taken for:

2015-1-MLT-002 P0 RSS (Observations of supernovae, near and far.)
2015-2-SCI-055 P2 HRS (Probing winds from the center of the Milky Way (@astrocrawford))
2015-2-SCI-021 P2 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-SCI-028 P2 RSS (Confirmation and redshift determination of galaxy clusters)
2015-2-COM-004 P2 HRS (Commissionning data for HRS)
2015-2-SCI-019 P2 RSS (Searching for binaries in unusual central stars of planetary nebulae )
2016-1-MLT-002 P3 HRS (x3) (Analysis of metallicity gradient and local chemical composition heterogeneity in the Galactic disk)
2016-1-SCI-025 P3 RSS (x8) (Spectral classification of rapidly pulsating stars)
2015-2-SCI-043 P4 RSS (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-17

SA: Marissa
SO: Thea
Others: Enrico

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Rained during the day. Heavy cloud until midnight. Brief clear bit and then struggled through thick clouds.

Data taken for:

2015-2-SCI-023 P1 HRS (HRS spectroscopy of eclipsing stars in Omega Centauri)
2015-2-SCI-019 P2 RSS (Searching for binaries in unusual central stars of planetary nebulae )
2015-2-SCI-021 P2 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-SCI-043 P4 RSS (x6) (Spectroscopic observations of bright RR Lyrae variables)
2015-2-SCI-056 P4 HRS (Tracing the chemical history of our galaxy)

Night Log 2016-04-16

SA: Marissa
SO: Thea
Others: Enrico, Elias. Anthony Mietas & 30 ASSA (Durban) visitors

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Too cloudy to open.

No data taken.

Night Log 2016-04-15

SA: Marissa
SO: Thea
Others: Enrico

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Sudden arrival of moonlit scattered clouds presented some challenges. Observed a polarimetry ToO that was added 04:00 p.m.

Data taken for:

2016-1-MLT-010 P0 RSS (Follow up observations of transient sources)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-1-MLT-002 P2 RSS (Observations of supernovae, near and far.)
2015-2-SCI-019 P2 RSS (Searching for binaries in unusual central stars of planetary nebulae )
2015-1-MLT-004 P2 RSS (Deriving the mass of the black holes in the core of active galaxies @romeroencarni1 @sand_dave)
2016-1-MLT-001 P3 RSS (x3) (Kinematics of Bulge Miras)
2015-2-SCI-028 P3 SCAM (Confirmation and redshift determination of galaxy clusters)
2015-2-SCI-056 P4 HRS (x2) (Tracing the chemical history of our galaxy)
2015-2-SCI-064 P4 SCAM (x2) (Studying the long-term behavior of classical novae after their eruptions)
2015-2-SCI-043 P4 RSS (x2) (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-14

SA: Marissa
SO: Thea
Others: Enrico. Lenka & Jantje visiting to see operations

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Clear night with decent seeing. Data taken for:

2015-2-SCI-023 P1 HRS (HRS spectroscopy of eclipsing stars in Omega Centauri)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-SCI-021 P2 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-COM-004 P2 HRS (Commissionning data for HRS)
2015-1-MLT-004 P2 RSS (Deriving the mass of the central super-massive black hole in the core of active galaxies)
2015-2-SCI-028 P3 SCAM (Confirmation and redshift determination of galaxy clusters)
2015-2-SCI-046 P3 RSS (A spectral study on low-mass T Tauri stars in the high mass star forming regions RCW 34 and NGC 2626)
2015-2-SCI-026 P3 RSS (Probing the time variability of QSO absorption line)
2015-2-SCI-064 P4 SCAM (Studying the long-term behavior of classical novae after their eruptions)
2015-2-SCI-056 P4 HRS (x2) (Tracing the chemical history of our galaxy)
2015-2-SCI-043 P4 RSS (x4) (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-13

SA: Marissa
SO: Thea
Others: Enrico

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Stable conditions with reasonable seeing once the night cleared up. It was put to productive use.

Data taken for:

2015-2-SVP-004 P0 RSS (Linear spectropolarimetric verificiation observations of a strongly polarized WD pulsator)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-COM-004 P2 HRS (x5) (Commissionning data for HRS)
2015-1-MLT-002 P2 RSS (Observations of supernovae, near and far.)
2015-2-SCI-019 P2 RSS (Searching for binaries in unusual central stars of planetary nebulae )
2015-2-SCI-026 P2 RSS (x2) (Probing the time variability of QSO absorption line)
2015-2-SCI-028 P3 SCAM (Confirmation and redshift determination of galaxy clusters)
2015-2-SCI-029 P3 RSS (x3) (Spectroscopy of Kepler K2 White Dwarfs)
2015-2-SCI-043 P4 RSS (x4) (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-12

SA: �ric
SO: Veronica
Others: Marissa, Enrico, Sudhanshu, Elias, Teresa, Simon and visitors.

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A fairly productive night.
We could obtain data for the following programs:

2015-2-SCI-055 P2 HRS (Probing winds from the center of the Milky Way (@astrocrawford))
2015-2-SCI-041 P3 RSS (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-SCI-029 P3 RSS (x8) (Spectroscopy of Kepler K2 White Dwarfs)
2015-2-SCI-056 P4 HRS (Tracing the chemical history of our galaxy)
2015-2-SCI-064 P4 SCAM (x2) (Studying the long-term behavior of classical novae after their eruptions)

Night Log 2016-04-11

SA: �ric
SO: Veronica
Others:

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A night with poor weather conditions : mostly cloudy.
But a night extremely productive. Thanks to many programs that required medium to poor conditions, and to the size of our mirror that allows us to litteraly observe through the clouds, we have gathered a huge amount of data, for many different kind of programs, ranging from measuring the chemical composition of the first stars in our Galaxy to measuring the kinematic of gas in a (beautiful) galaxy located 4,5 mega parsecs (that is approximatively 15 million light years) from us: M83.
We have observed the following programs:
2015-2-SCI-008 P1 HRS (Determining the period of a multi-periodic pulsating binary system.)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-SCI-029 P3 RSS (x7) (Spectroscopy of Kepler K2 White Dwarfs)
2015-2-SCI-063 P3 SCAM (Studying the long-term behavior of classical novae after their eruptions)
2015-2-SCI-043 P4 RSS (x13) (Spectroscopic observations of bright RR Lyrae variables)
2015-2-SCI-056 P4 HRS (x3) (Tracing the chemical history of our galaxy)

Night Log 2016-04-10

SA: �ric
SO: Veronica
Others:

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A very productive night. Overall good conditions, and no technical problems.
We have obtained data for the following programs:
2015-2-SVP-004 P0 RSS (Linear spectropolarimetric verificiation observations of a strongly polarized WD pulsator)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-SCI-024 P1 RSS (Fabry-Perot observations to trace the narrow line regions in nearby Seyfert 2s)
2015-2-SCI-008 P1 HRS (Determining the period of a multi-periodic pulsating binary system.)
2015-2-SCI-059 P2 RSS (RESOLVE survey kinematics observations)
2015-1-MLT-002 P2 RSS (Observations of supernovae, near and far.)
2015-1-MLT-004 P2 RSS (Deriving the mass of the central super-massive black hole in the core of active galaxies)
2015-2-SCI-029 P3 RSS (x4) (Spectroscopy of Kepler K2 White Dwarfs)
2015-2-SCI-041 P3 RSS (x2) (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-SCI-064 P4 SCAM (Studying the long-term behavior of classical novae after their eruptions)

Night Log 2016-04-09

SA: �ric
SO: Veronica
Others:

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A productive night, with good conditions during most part of the night, and towards the very end, humidity had us close.

We have passed for the first time ever the 1000 blocks observed during one semester! And there are three more weeks to go.

Data gathered for :
2015-2-SVP-004 P0 RSS (Linear spectropolarimetric verificiation observations of a strongly polarized WD pulsator)
2015-2-SCI-021 P1 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-SCI-008 P1 HRS (Determining the period of a multi-periodic pulsating binary system.)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-SCI-041 P2 RSS (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-COM-004 P2 HRS (Commissionning data for HRS)
2015-2-SCI-031 P2 RSS (Connecting QSO absorption line systems with the associated galaxies)
2015-2-SCI-029 P3 RSS (x4) (Spectroscopy of Kepler K2 White Dwarfs)
2015-2-SCI-064 P4 SCAM (x2) (Studying the long-term behavior of classical novae after their eruptions)

Night Log 2016-04-08

SA: �ric
SO: Veronica
Others:

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The night started with excellent seeing : the first measurement was 0.68, and it stayed around 0.8 for most of the time we stayed open.
But then, humidity forced us to close.
We could gather data for:
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-SCI-028 P2 RSS (Confirmation and redshift determination of galaxy clusters)
2015-2-SCI-041 P3 RSS (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-SCI-029 P3 RSS (Spectroscopy of Kepler K2 White Dwarfs)

Night Log 2016-04-07

SA: �ric
SO: Veronica
Others:

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A productive first half of the night, and then, humidity forced us to close
We could get data for the following programs:
2015-2-SVP-004 P0 RSS (Linear spectropolarimetric verificiation observations of a strongly polarized WD pulsator)
2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-COM-004 P2 HRS (Commissionning data for HRS)
2015-2-SCI-041 P2 RSS (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-SCI-026 P3 RSS (x2) (Probing the time variability of QSO absorption line)
2015-2-SCI-029 P3 RSS (x3) (Spectroscopy of Kepler K2 White Dwarfs)

Night Log 2016-04-06

SA: �ric
SO: Veronica
Others: Ted on skype for FP

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Summary
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No scientific data gathered tonight, the weather was particularly uncooperative. Very high wind at the beginning of the night, and then, humidity, and then clouds.

Night Log 2016-04-05

SA: Petri
SO: Thea
Others: Eric, Veronica

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Summary
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Lost the whole night to high humidity and clouds, no science data taken.

Night Log 2016-04-04

SA: Petri
SO: Thea
Others:

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Summary
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A swift beginning to the night with several observations done in clear
and good seeing conditions. Then humidity closed us up. Data for:

2015-2-SCI-004 P1 RSS (x2) (A kinematic study of extraplanar diffuse ionized gas in the galaxy M83)
2015-2-SCI-028 P2 RSS (Confirmation and redshift determination of galaxy clusters)
2015-2-SCI-059 P3 RSS (x2) (RESOLVE survey kinematics observations)
2015-2-SCI-043 P4 RSS (Spectroscopic observations of bright RR Lyrae variables)

Night Log 2016-04-03

SA: Petri
SO: Thea
Others: Ted and Blaise over skype, Eben on phone

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Summary
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Mostly clear night, until the end. Mostly decent seeing, except
the beginning. Observed the full night - mostly without RSS,
however. Many good data sets taken, both science and some
engineering, for:

2015-2-SCI-021 P1 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-COM-004 P2 HRS (x4) (Commissionning data for HRS)
2015-2-SCI-028 P3 SCAM (x4) (Confirmation and redshift determination of galaxy clusters)
2015-2-SCI-063 P3 SCAM (Studying the long-term behavior of classical novae after their eruptions)
2015-2-SCI-049 P4 RSS (Monitoring the X-ray bright sgB[e] stars in Magellanic Clouds)
2015-2-SCI-064 P4 SCAM (Studying the long-term behavior of classical novae after their eruptions)
2015-2-SCI-043 P4 RSS (Spectroscopic observations of bright RR Lyrae variables)
2015-2-SCI-056 P4 HRS (x2) (Tracing the chemical history of our galaxy)

Night Log 2016-04-02

SA: Petri
SO: Thea
Others: Ted and Encarni on skype

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Summary
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A crystal clear dark night with reasonably good seeing. Night full of
science. Also, did a successful dual-etalon mode Fabry-Perot
observation, and added more spectropolarimetric testing in engineering
time. Lost a bit of time right at the end of the night to a tech problem
otherwise a great night. Data taken for:

2015-2-COM-003 P0 RSS (Polarimetry test proposal)
2015-2-SCI-021 P1 HRS (x2) (High resolution spectroscopic abundance measurements of RGBs in NGC 6584)
2015-2-SCI-024 P1 RSS (Fabry-Perot observations to trace the narrow line regions in nearby Seyfert 2s)
2015-2-SCI-035 P1 RSS (Identifying new ultracompact binary star systems through their spectral characteristics)
2015-2-SVP-001 P1 RSS (RSS-FP R commissioning)
2015-2-SCI-048 P2 RSS (x2) (DIBs towards the Red Rectangle - Fabry-Perot)
2015-2-SCI-041 P2 RSS (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-SCI-059 P2 RSS (RESOLVE survey kinematics observations)
2015-2-SCI-028 P3 SCAM (Confirmation and redshift determination of galaxy clusters)

Night Log 2016-04-01

SA: Petri
SO: Thea
Others: Ted and Encarni over skype

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Summary
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The full night lost to clouds and humidity. However, got some semi-useful
Fabry-Perot testing done on-sky through the gaps in clouds in the
beginning part of the night. No "accepted" science data produced.

Night Log 2016-03-31

SA: Petri
SO: Thea
Others:

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Summary
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A very nice clear problem-free night with sub-arcsec seeing.
Humidity went steadily up however until we had to close at around
3am. Until then, many science observations with shorter engineering
observations in between. Data for:

2015-2-MLT-004 P1 RSS (Unraveling ring galaxies)
2015-2-SCI-024 P1 RSS (x2) (Fabry-Perot observations to trace the narrow line regions in nearby Seyfert 2s)
2015-2-COM-004 P2 HRS (x5) (Commissionning data for HRS)
2015-1-MLT-004 P2 RSS (Deriving the mass of the central super-massive black hole in the core of active galaxies)
2015-2-SCI-041 P2 RSS (Spectroscopic classification of candidate magnetic cataclysmic variables in the CRTS)
2015-2-SCI-012 P3 RSS (Searching for a companion to the eclipsing binary 1SWASP J161253.63-022042.2)