Laboratorium Astrofisika

Astrophysics Laboratory
 

  “Life is either a daring adventure or nothing.”

"Hidup adalah petualangan yang membutuhkan keberanian, bila tidak itu bukanlah hidup."

Harvard-Smithsonian Center for Astrophysics
60 Garden Street, Cambridge, MA 02138

H-R Diagram of M67 using the Clay Telescope

 
 

Instructors: Allyson Bieryla and Jonathan Grindlay

The Clay Telescope is located on the roof of the Science Center. It is a 16" telescope equipped with a CCD (charged coupled device) imager. This project is divided into three main parts. First you will learn to use the telescope to observe and image the open cluster M67 in B and V filters. We will probably need no more than three nights of observing to accomplish this, but that is just an estimate. We will then learn how to process the images using IRAF (Image Reduction and Analysis Facility) software. 

This software will enable us the tools to reduce the data, subtracting away the inherent biases of observing. We will also use IRAF to do the actual photometry to determine the magnitudes of the stars in the cluster in both B and V fields. Finally we will create an Hertzsprung-Russell diagram, which plots the V magnitude vs. B-V magnitude. This shows where the stars in the cluster are on the main sequence. From this diagram, we can estimate the cluster's age and determine the approximate distance to the cluster. Also, knowing the angular width of the CCD image and the distance to cluster, we can approximate the number of stars in a single image to get a rough density of stars in the cluster. 

Laboratory Astrophysics

Science is successful because the physical laws we discover on Earth work everywhere and every when. We use laboratory experiments to expand our understanding of physical processes and then apply these results to the processes throughout the Universe. In some cases laboratory experiments can reproduce similar physics. For example, highly charged plasmas can be created in the laboratory to study the collisions between electrons and ions that occur in the hot solar corona. In other cases, such as in the extreme environments of black holes, we cannot reproduce the conditions. However, even in those cases, the pattern of observed spectral signatures allows us to identify the species and determine some of the physical conditions and processes. Spectral features observed in the solar corona are also observed from black hole sources.  

Useful Link

• ADS Bibliographic databases, an essential tool of modern astronomers
  
  
• astro-ph Astronomy e-prints
  
  
• Astronomy Picture of the Day - never disappoints
  
  
• Chandra Coordinate Conversion and Precession Tool
  
  
• Clear Sky Clock - best local cloud forecaster
  
  
• SkyView - virtual telescope
  
  
• AstroWeb - Guide to astronomy on the internet
  
  
• AAS American Astronomical Society
  
  
• Handbook of Space Astronomy and Astrophysics by Martin V. Zombeck
  
  
• Research links from Harvard Department of Astronomy

 

COSMIC RAY ACCELERATION AT BLAST WAVES FROM TYPE Ia SUPERNOVAE

By: HYESUNG KANG

Department of Earth Sciences, Pusan National University, Pusan 609 -735, Korea

E-mail: hskang@pusan.ac.kr

(Received November 10, 2006; Accepted December 6, 2006)

ABSTRACT

We have calculated the cosmic ray (CR) acceleration at young remnants from Type Ia supernovae expanding into a uniform interstellar medium (ISM). Adopting quasi-parallel magnetic fields, gasdynamic equations and the diffusion convection equation for the particle distribution function are solved in a comoving spherical grid which expands with the shock. Bohm-type diffusion due to self-excited Alfv´en waves, drift and dissipation of these waves in the precursor and thermal leakage injection were included. With magnetic fields amplified by the CR streaming instability, the particle energy can reach up to 10 16 Z eV at young supernova remnants (SNRs) of several thousand years old. The fraction of the explosion energy transferred to the CR component asymptotes to 40-50 % by that time. For a typical SNR in a warm ISM, the accelerated CR energy spectrum should exhibit a concave curvature with the power-law slope flattening from 2 to 1.6 at E > ∼ 0.1 TeV. Key Words : cosmic ray acceleration – supernova remnants – hydrodynamics – methods:numerical

http://arxiv.org/pdf/astro-ph/0701027.pdf

Nobel Prize in Physics 2010

Photo: U. Montan

Andre Geim

 

Photo: U. Montan

Konstantin Novoselov

The Nobel Prize in Physics 2010 was awarded jointly to Andre Geim and Konstantin Novoselov

 

"for groundbreaking experiments regarding the two-dimensional material graphene"

The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2010 to

Andre Geim
University of Manchester, UK
and
Konstantin Novoselov
University of Manchester, UK
"for groundbreaking experiments regarding the two-dimensional material graphene"

 

Graphene – the perfect atomic lattice

A thin flake of ordinary carbon, just one atom thick, lies behind this year’s Nobel Prize in Physics. Andre Geim and Konstantin Novoselov have shown that carbon in such a flat form has exceptional properties that originate from the remarkable world of quantum physics.

Graphene is a form of carbon. As a material it is completely new – not only the thinnest ever but also the strongest. As a conductor of electricity it performs as well as copper. As a conductor of heat it outperforms all other known materials. It is almost completely transparent, yet so dense that not even helium, the smallest gas atom, can pass through it. Carbon, the basis of all known life on earth, has surprised us once again.

Geim and Novoselov extracted the graphene from a piece of graphite such as is found in ordinary pencils.

Using regular adhesive tape they managed to obtain a flake of carbon with a thickness of just one atom. This at a time when many believed it was impossible for such thin crystalline materials to be stable.

However, with graphene, physicists can now study a new class of two-dimensional materials with unique properties. Graphene makes experiments possible that give new twists to the phenomena in quantum physics. Also a vast variety of practical applications now appear possible including the creation of new materials and the manufacture of innovative electronics. Graphene transistors are predicted to be substantially faster than today’s silicon transistors and result in more efficient computers.

Since it is practically transparent and a good conductor, graphene is suitable for producing transparent touch screens, light panels, and maybe even solar cells.

When mixed into plastics, graphene can turn them into conductors of electricity while making them more heat resistant and mechanically robust. This resilience can be utilised in new super strong materials, which are also thin, elastic and lightweight. In the future, satellites, airplanes, and cars could be manufactured out of the new composite materials.

This year’s Laureates have been working together for a long time now. Konstantin Novoselov, 36, first worked with Andre Geim, 51, as a PhD-student in the Netherlands. He subsequently followed Geim to the United Kingdom. Both of them originally studied and began their careers as physicists in Russia. Now they are both professors at the University of Manchester.

Playfulness is one of their hallmarks, one always learns something in the process and, who knows, you may even hit the jackpot. Like now when they, with graphene, write themselves into the annals of science. 

Read more about this year's prize

Information for the Public

Scientific Background Pdf 1 MB

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Links and Further Reading

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Andre Geim, Dutch citizen. Born 1958 in Sochi, Russia. Ph.D. 1987 from Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, Russia. Director of Manchester Centre for Meso-science & Nanotechnology, Langworthy Professor of Physics and Royal Society 2010 Anniversary Research Professor, University of Manchester, UK.

www.condmat.physics.manchester.ac.uk/people/academic/geim

Konstantin Novoselov, British and Russian citizen. Born 1974 in Nizhny Tagil, Russia. Ph.D. 2004 from Radboud University Nijmegen, The Netherlands. Professor and Royal Society Research Fellow, University of Manchester, UK.

www.condmat.physics.manchester.ac.uk/people/academic/novoselov

Prize amount: SEK 10 million to be shared equally between the Nobel Laureates.