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Portal:Radiation astronomy

Radiation astronomy
This image is a composite of several types of radiation astronomy: radio, infrared, visual, ultraviolet, soft and hard X-ray. Credit: NASA.

Radiation astronomy is astronomy applied to the various extraterrestrial sources of radiation, especially at night. It is also conducted above the Earth's atmosphere and at locations away from the Earth, by satellites and space probes, as a part of explorational (or exploratory) radiation astronomy.

Seeing the Sun and feeling the warmth of its rays is probably a student's first encounter with an astronomical radiation source. This will happen from a very early age, but a first understanding of the concepts of radiation may occur at a secondary educational level.

Radiation is all around us on top of the Earth's crust, regolith, and soil, where we live. The study of radiation, including radiation astronomy, usually intensifies at the university undergraduate level.

And, generally, radiation becomes hazardous, when a student embarks on graduate study.

Cautionary speculation may be introduced unexpectedly to stimulate the imagination and open a small crack in a few doors that may appear closed at present. As such, this learning resource incorporates some state-of-the-art results from the scholarly literature.

The laboratories of radiation astronomy are limited to the radiation observatories themselves and the computers and other instruments (sometimes off site) used to analyze the results.

Selected resource
The simulation attempts to answer how thunderstorms launch particle beams into space. Credit: NASA/Goddard Space Flight Center.

A number of subatomic reactions can be detected in Draft:astronomy that yield beta particles. The detection of beta particles or the reactions that include them in an astronomical situation is beta-particles astronomy.

Notation: let TGF stand for a Terrestrial Gamma-ray Flash.

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Selected lecture

Strong forces

"In field theory it is known that coupling constants “run”. This means that the values of the coupling constants that one measures depend on the energy at which the measurement is performed. [...] the three different coupling constants [one each for the strong force, electromagnetic force, and the weak force] of the standard model seem to converge to the same value at an energy scale of about 1016 GeV [...] This suggests that there is only one coupling constant at high energies and most likely only one symmetry group. [...] The current belief [is] that the electromagnetic, weak and strong forces [are] unified at about 1016 GeV [as such] one has to rely on [the] particle physics interactions which can lead to electromagnetic radiation and cosmic rays".[1]

References

  1. Tanmay Vachaspati (1998). "Topological defects in the cosmos and lab". Contemporary Physics 39 (4): 225-37. doi:10.1080/001075198181928. http://www.tandfonline.com/doi/abs/10.1080/001075198181928. Retrieved 2013-11-05. 
Selected theory

Stellar surface fusion

RHESSI observes high-energy phenomena from a solar flare. Credit: NASA/Goddard Space Flight Center Scientific Visualization Studio.

Stellar surface fusion occurs above a star's photosphere to a limited extent as found in studies of near coronal cloud activity.

Surface fusion is produced by reactions during or preceding a stellar flare and at much lower levels elsewhere above the photosphere of a star.

"Nuclear interactions of ions accelerated at the surface of flaring stars can produce fresh isotopes in stellar atmospheres."[1]

"This energy [1032 to 1033 ergs] appears in the form of electromagnetic radiation over the entire spectrum from γ-rays to radio burst, in fast electrons and nuclei up to relativistic energies, in the creation of a hot coronal cloud, and in large-scale mass motions including the ejections of material from the Sun."[2]

"The new reaction 208Pb(59Co,n)266Mt was studied using the Berkeley Gas-filled Separator [BGS] at the Lawrence Berkeley National Laboratory [LBNL] 88-Inch Cyclotron."[3]

266Mt has been produced using the 209Bi(58Fe,n)266Mt reaction.[3]

"Reactions with various medium-mass projectiles on nearly spherical, shell-stabilized 208Pb or 209Bi targets have been used in the investigations of transactinide (TAN) elements and their decay properties for many years. These so-called “cold fusion” reactions produce weakly excited (10-15 MeV) [1] compound nuclei (CNs) at bombarding energies at or near the Coulomb barrier that de-excite by the emission of one to two neutrons."[3]

"The laboratory-frame, center-of-target energy used was 291.5 MeV, corresponding to a CN excitation energy of 14.9 MeV."[3]

"At the start of the experiment the BGS magnet settings were chosen to guide products with a magnetic rigidity of 2.143 T·m to the center of the [focal plane detector] FPD. After the first event of 266Mt was detected in strip 45 (near one edge of the FPD), the magnetic field strength was decreased to 2.098 T·m in an effort to shift the distribution of products toward the center of the detector."[3]

"258Db [has been produced] via the 209Bi(50Ti,n) and 208Pb(51V,n) reactions [15], and 262Bh via the 209Bi(54Cr,n) and 208Pb(55Mn,n) reactions [13, 16]."[3]

"Hofmann et al. at Gesellschaft für Schwerionenforschung (GSI) in Darmstadt, Germany, and Morita et al., at the Institute of Physical and Chemical Research (RIKEN) in Saitama, Japan, have studied the 209Bi(64Ni,n)272Rg reaction [7, 17, 18]. The complementary 208Pb(65Cu,n)272Rg reaction was studied by Folden et al. at the Lawrence Berkeley National Laboratory (LBNL) [19]."[3]

"Based on the observation of the long-lived isotopes of roentgenium, 261Rg and 265Rg (Z = 111, t1/2 ≥ 108 y) in natural Au, an experiment was performed to enrich Rg in 99.999% Au. 16 mg of Au were heated in vacuum for two weeks at a temperature of 1127°C (63°C above the melting point of Au). The content of 197Au and 261Rg in the residue was studied with high resolution inductively coupled plasma-sector field mass spectrometry (ICP-SFMS). The residue of Au was 3 × 10−6 of its original quantity. The recovery of Rg was a few percent. The abundance of Rg compared to Au in the enriched solution was about 2 × 10−6, which is a three to four orders of magnitude enrichment."[4]

References

  1. Vincent Tatischeff, J.-P. Thibaud, I. Ribas (January 2008). "Nucleosynthesis in stellar flares". eprint arXiv:0801.1777. http://arxiv.org/pdf/0801.1777. Retrieved 2012-11-09. 
  2. R. P. Lin and H. S. Hudson (September-October 1976). "Non-thermal processes in large solar flares". Solar Physics 50 (10): 153-78. doi:10.1007/BF00206199. http://adsabs.harvard.edu/full/1976SoPh...50..153L. Retrieved 2013-07-07. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 S. L. Nelson, K. E. Gregorich, I. Dragojević, J. Dvořák, P. A. Ellison, M. A. Garcia, J. M. Gates, L. Stavsetra, M. N. Ali, and H. Nitsche (February 25, 2009). "Comparison of complementary reactions in the production of Mt". Physical Review C 79 (2): e027605. doi:10.1103/PhysRevC.79.027605. http://prc.aps.org/abstract/PRC/v79/i2/e027605. Retrieved 2014-04-07. 
  4. A. Marinov, A. Pape, D. Kolb, L. Halicz, I. Segal, N. Tepliakov and R. Brandt (2011). "Enrichment of the Superheavy Element Roentgenium (Rg) in Natural Au". International Journal of Modern Physics E 20 (11): 2391-2401. doi:10.1142/S0218301311020393. http://www.phys.huji.ac.il/~marinov/publications/Rg_261_arXiv_77.pdf. Retrieved 2014-04-08. 
Selected topic

Emissions

The Hubble Space Telescope [Advanced Camera for Surveys] ACS image has H-alpha emission of the Red Rectangle shown in blue. Credit: ESA/Hubble and NASA.

"[T]he extended red emission (ERE) [is] observed in many dusty astronomical environments, in particular, the diffuse interstellar medium of the Galaxy. ... silicon nanoparticles provide the best match to the spectrum and the efficiency requirement of the ERE."[1]

References

  1. Adolf N. Witt, Karl D. Gordon and Douglas G. Furton (July 1, 1998). "Silicon Nanoparticles: Source of Extended Red Emission?". The Astrophysical Journal Letters 501 (1): L111-5. doi:10.1086/311453. http://iopscience.iop.org/1538-4357/501/1/L111. Retrieved 2013-07-30. 
Objects
Selected image
Gigantic jet near Phillipines.png

This is an image of a gigantic jet above a thunderstorm near the Philippines. Credit: H. T. Su, R. R. Hsu, A. B. Chen, Y. C. Wang, W. S. Hsiao, W. C. Lai, L. C. Lee, M. Sato & H. Fukunishi.

Selected lesson

First red source in Canis Major

Sirius is the brightest star as seen from Earth, apart from the Sun. Credit: Mellostorm.

The first red source in Canis Major is unknown.

This is a lesson in map reading, coordinate matching, and researching. It is also a research project in the history of red astronomy looking for the first astronomical red source discovered in the constellation of Canis Major.

Nearly all the background you need to participate and learn by doing you've probably already been introduced to at a secondary level.

Some of the material and information is at the college or university level, and as you progress in finding red sources, you'll run into concepts and experimental tests that are actual research.

To succeed in finding a red source in Canis Major is the first step.

Next, you'll need to determine the time stamp of its discovery and compare it with any that have already been found. Over the history of red astronomy a number of sources have been found, many as point sources in the night sky. These points are located on the celestial sphere using coordinate systems. Familiarity with these coordinate systems is not a prerequisite. Here the challenge is geometrical, astrophysical, and historical.

Selected quiz

Electromagnetic radiation astronomy quiz

A new image from all three of NASA's Great Observatories--Chandra, Hubble, and Spitzer--has been created of the star-forming region 30 Doradus, also known as the Tarantula Nebula. Credit: NASA.

Electromagnetic astronomy is a lecture from the astronomy department.

This is a quiz based on the lecture that you are free to take at any time or knowledge level.

Once you’ve read and studied the lecture itself, the links contained within the article and lecture, listed under See also and External links, you should have adequate background to take the quiz and score highly. The templates {{astronomy resources}} and {{principles of radiation astronomy}} may also be helpful.

As a "learning by doing" resource, this quiz helps you to assess your knowledge and understanding of the information, and it is a quiz you may take over and over as a learning resource to improve your knowledge, understanding, test-taking skills, and your score.

Suggestion: Have the lecture available in a separate window.

Enjoy learning by doing!

Selected laboratory

Cosmogony laboratory

This is an image of Chaos magnum from a book. Credit: Sailko.

This laboratory is an activity for you to create a universe. While it is part of the astronomy course principles of radiation astronomy, it is also independent.

Some suggested primordial entities to consider are electromagnetic radiation, neutrinos, mass, time, Euclidean space, Non-Euclidean space, dark matter, dark energy, purple phantoms, and spacetime.

More importantly, there are your primordial entities.

And, yes, you can create a universe from a peanut butter and jelly sandwich if you wish to.

You may choose to define your primordial entities or not.

Usually, research follows someone else's ideas of how to do something. But, in this laboratory you can create these too.

This is an astronomy cosmogony laboratory, but you may create what an astronomy, a cosmogony, or a laboratory is.

Yes, this laboratory is structured. And, you are providing it. Or, not, an unstructured universe is okay too.

I will provide an example of a cosmogony. The rest is up to you.

Questions, if any, are best placed on the discussion page. Please put your laboratory results, you'd like evaluated, on the laboratory's discussion page.

Selected problems

Angular momentum and energy

This diagram describes the relationship between force (F), torque (τ), momentum (p), and angular momentum (L) vectors in a rotating system. 'r' is the radius. Credit: Yawe.

Angular momentum and energy are concepts developed to try to understand everyday reality.

An angular momentum L of a particle about an origin is given by

where r is the radius vector of the particle relative to the origin, p is the linear momentum of the particle, and × denotes the cross product (r · p sin θ). Theta is the angle between r and p.

Please put any questions you may have, and your results, you'd like evaluated, on the problem set's discussion page.

Enjoy learning by doing!

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