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not_course_2018:projects

Projects

1a Spectroscopy of galaxy clusters

Supervisors: Alexis Finoguenov, Charles Kirkpatrick (Helsinki)
Observations: ALFOSC imaging + MOS (and/or long-slit) spectroscopy

Abstract:
Availability of spectroscopic redshift information on galaxy clusters serves to a broad range of cosmology applications. It removes the uncertainties and biases associated with the photometric redshifts, which otherwise propagate into all subsequent cluster characterisation. It is a key measurement to assess the structure of clusters and their surroundings. Finally, it enables clustering studies, providing a test of the scale-dependent growth of structure, important for testing the Einstein theory of gravity. Students of this group will learn how to conduct and analyze such observations.
We have two distinct projects that employ the spectroscopic observations on NOT. Group 1 will carry out detailed spectroscopic studies of intermediate redshift clusters to characterize the cluster dynamics. The observations are used to compute the velocity dispersion of clusters, with about 30 spectra to be measured per cluster. The exposure is selected to enable the spectral analysis for the faintest member.
Backup/filler program:
The CODEX subsample being followed-up by SPIDERS (SDSS-IV program) contains 20% of clusters with high spectroscopic incompleteness. Some of the clusters miss the brightest cluster galaxy. By performing the program, we will both improve the identification and learn about the star-formation activity of BCG. Dark time is prefered by this program. The students will learn how to put many galaxies on a single slit.

1b NIR imaging of a molecular cloud core in the Herschel field G159.23-34.51

Supervisors: Mika Saajasto, Mika Juvela (Helsinki)
Observations: NOTCAM near-IR imaging

Abstract
We propose near-infrared (NIR) imaging of a nearby (d=325 pc) molecular cloud G159.23-43.51 targeted already in the Herschel project Galactic Cold Cores and in Spitzer project Star Formation and Structure in two High-Latitude Molecular Clouds. Our study is concerned with the initial stages of star formation. NOTCam J and Ks band data will be used to derive an estimate of NIR extinction that complement our Herschel data and help to determine the structure and stability of the cores. NOTCam measurements of scattered light provide information on the radiation field and NIR dust properties. With Spitzer mid-infrared data of the coreshine phenomenon, these will be used to determine dust properties and especially to measure grain growth. The results on grain coagulation are relevant for the chemistry and thermal balance of cloud cores in general. By dening the initial conditions for later evolution, the results have important implications even for protostellar disks and the ensuing planet formation.

Students: Paolo Calabretto, Soetkin Janssens, Tuomas Salo, Juha-Pekka Virtanen

2a Spectroscopy of galaxy clusters 2

Supervisors: Alexis Finoguenov, Charles Kirkpatrick (Helsinki)
Observations: ALFOSC imaging + MOS (and/or long-slit) spectroscopy

Abstract:
Availability of spectroscopic redshift information on galaxy clusters serves to a broad range of cosmology applications. It removes the uncertainties and biases associated with the photometric redshifts, which otherwise propagate into all subsequent cluster characterisation. It is a key measurement to assess the structure of clusters and their surroundings. Finally, it enables clustering studies, providing a test of the scale-dependent growth of structure, important for testing the Einstein theory of gravity. Students of this group will learn how to conduct and analyze such observations.
We have two distinct projects that employ the spectroscopic observations on NOT. Group 2 will work on confirmation of high-z clusters. The project aims at identification of 5 spectroscopic cluster members, which would reveal the cluster redshift. The target galaxies are faint and require deep exposures to get enough members. Backup/filler program:
The CODEX subsample being followed-up by SPIDERS (SDSS-IV program) contains 20% of clusters with high spectroscopic incompleteness. Some of the clusters miss the brightest cluster galaxy. By performing the program, we will both improve the identification and learn about the star-formation activity of BCG. Dark time is prefered by this program. The students will learn how to put many galaxies on a single slit.

2b NIR imaging of a molecular cloud core in the Herschel field G159.23-34.51

Supervisors: Mika Saajasto, Mika Juvela (Helsinki)
Observations: NOTCAM near-IR imaging

Abstract
We propose near-infrared (NIR) imaging of a nearby (d=325 pc) molecular cloud G159.23-43.51 targeted already in the Herschel project Galactic Cold Cores and in Spitzer project Star Formation and Structure in two High-Latitude Molecular Clouds. Our study is concerned with the initial stages of star formation. NOTCam J and Ks band data will be used to derive an estimate of NIR extinction that complement our Herschel data and help to determine the structure and stability of the cores. NOTCam measurements of scattered light provide information on the radiation field and NIR dust properties. With Spitzer mid-infrared data of the coreshine phenomenon, these will be used to determine dust properties and especially to measure grain growth. The results on grain coagulation are relevant for the chemistry and thermal balance of cloud cores in general. By dening the initial conditions for later evolution, the results have important implications even for protostellar disks and the ensuing planet formation.

Students: Jussi Ahoranta, Mikko Pöntinen, Sanna Damsted, Jani-Matti Hätinen

3. Optical photometry and spectroscopy and time-resolved NIR photometry of interacting binary stars

Supervisor: Vitaly Neustroev (Oulu)
Observations: ALFOSC imaging + spectroscopy, NOTCam imaging

Abstract:
We will obtain optical spectra of two low-mass X-ray binaries (LNXBs). The students will reduce the spectra and try to detect qualitative and quantitative changes in them, compared with those I obtained 2 and 1 months ago with the NOT and ESO/NTT telescopes. We will also obtain optical images with different filters of a few cataclysmic variables (CVs) in order to obtain their Spectral Energy Distribution (SED) in quiescence. We will also try to detect an orbital variability in near-infrared wavelengths in 1 or 2 of these CVs. For this, we will obtain time-resolved photometry with NOTCam.

Backup data: similar observations were obtained during previous schools.

Students: Miikka Siitonen, Ixaka Labadie, Anastasiia Ershova, Jussi Hedemäki

4. Dust in gamma-ray BL Lac host galaxies

Supervisor: Kari Nilsson (FINCA)
Observations: ALFOSC imaging and long-slit spectroscopy, NOTCam imaging

Abstract:
This is a short observing program to check the feasibility of detecting dust in BL Lacertae host galaxies. We will concentrate on one BL Lac which clearly shows a dust lane in the optical plus a few candidates and one or two control targets. We will use BVIJH imaging plus existing R-band data to study the colors of the host galaxies and study the presence of dust from there.

Students: Joonas Kujala, Petri Numminen, Philipp Oleynik, Joonas Tarvainen, Juuso Uusimäki

not_course_2018/projects.txt · Last modified: 2018/10/27 17:37 by teacher