What is Spectra: Definition and 283 Discussions

Bantam Spectra is the science fiction division of American publishing company Bantam Books, which is owned by Random House.
According to their website, Spectra publishes "science fiction, fantasy, horror, and speculative novels from recognizable authors". Spectra authors have collectively won 31 such awards in the fields of science fiction and fantasy, and been nominated on 132 occasions. These authors include the following:

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  1. I

    Graph absorption spectra of 2,3-dimethylindole?

    Can anyone send me a picture of graph absorption spectra of 2,3-dimethylindole? The graph should be accurate (from a spectrophotometer) Thanks
  2. E

    Determining Signal Spectra from Fourier Transform: 100 kHz Impulse Train

    Hello there, if I have a impulse train as f(t) with a frequency of 100 khz, and cos(w_0*t) = g(t) with frequency of 10 khz, how do I go about determining the signal spectra, (i.e. harmonics n = 1,2,3...)? I determined the Fourier transform, but I get stuck as to what to do with it. :confused...
  3. U

    Trying to understand a reading on Moseley and the X-ray Spectra

    I was wondering why Henry Moseley ploted \sqrt{f} vs. Z instead of just f vs. Z. I'm guessing it is because this way, the graph of \sqrt{f} vs. Z would be linear? But if it was just f vs. Z, wouldn't the equation just be exponential? Also, what is the significance of the L seriese and the K...
  4. R

    Understanding the Mathematical Definition of the State Ket Expansion in Sakurai

    In Sakurai: The state ket for an arbitrary physical state can be expanded in terms of the |x'> |\alpha>=\int dx'^3 |\mathbf{x'}><\mathbf{x'}|\alpha> (where the |x'> are the eigenkets of the position operator, \hat{x}|x'>=x'|x'>). (Sakurai 1.6.4, p. 42) My question is about how this integral is...
  5. Q

    Atomic spectra evidence for relativistic potential

    In L. I. Schiff book, one can follow his derivation of the Hamiltonian from Dirac relativistic equation and obtain the following.. \left[\frac{\vec{p}^2}{2m}+V-\frac{\hbar^2}{4m^{2}c^{2}}\frac{dV}{dr}\frac{\partial}{\partial r}+\frac{1}{2m^{2}c^{2}}\frac{1}{r}\frac{dV}{dr}\vec{S}\cdot...
  6. M

    Complex Fourier Series and Phase Spectra

    Please check my solution and I need help on understanding the second part of the question. Q:Obtain the complex form of the Fourier series of the sawtooth function. f(t) = \frac{2t}{T} \ \ \ 0 < t < 2T\\ So if the period is 2l = 2T then l = T \\ c_n = \frac{1}{2l} \int_{-l}^{l} f(x) e^{in\pi...
  7. U

    How does the line spectra work?

    i'm about to tear off all the hair on my head, learning about line spectra... i got the lyman,balmer and paschen series in my textbook and the formula for it. but how do i apply it in a physics question? like for example if i have an electron that is excited to the n = 6 state, which formula...
  8. S

    Exploring Atomic Emission Spectra: Neon vs Helium & Electron Configuration

    Why does neon have more spectral lines than helium? Is the atomic spectrum based on an element's electron configuration?
  9. G

    Atomic spectra and atomic structure by Gerhard Herzberg

    Hi! to everyone on the forum. I am new and did not really know where i should of posted this thread its not homework its just a question i have. A friend of mine asked me a question about a book he read about (atomic spectra and atomic structure by Gerhard Herzberg). Gerhard Herzberg said...
  10. chem_tr

    19F-NMR Spectra Recording with Trifluoroacetic Acid Reference

    Hello, A friend of mine has synthesized a compound with pentafluorophenyl groups, and is willing to characterize it via an additional 19F-NMR. However, the person responsible for recording NMR spectra is inexperienced in 19F-NMR, so we need help on recording the spectra. We have...
  11. J

    Lyman Alpha Photons in Visible, UV, X-Ray & Gamma Ray Spectra

    Consider the Lyman photons for Hydrogen-like atoms with Z greater than one. Which of these atoms have Lyman alpha photons in the 1)visible 2)UV 3)X-ray and 4)gamma-ray parts of the spectrum? Can list ranges of values of Z in the answers. My thoughts are to use 1/lambda=...
  12. D

    Question on stellar absorption spectra

    Why don't stellar spectra show absorption lines for carbon, oxygen or nitrogen if they are such abundant elements. Is there a 'spectral type' that does? Thanks Dave
  13. Q

    Why do molecules have rotational Raman spectra?

    Hi all, i am studying the physics of Raman Spectra. Was able to understand the origin of Vibrational Raman Spectra... which was an effect due to the change of polarizability with internuclear distance due to molecular vibration. But, i still yet to figure out why rotation of molecules can...
  14. S

    Static Universe Theroy and Red shifts in galaxy spectra

    Hi, i have a question, if we imaging that the universe is static and not expanding, what observation would be made in regards to red shifts in galaxy spectra?
  15. S

    Understanding X-Ray Spectra Graphs

    just been learning how to produce x-rays by firing electrons at heavy atoms, but i am a tad confused about the x-ray spectra graph with 'intensity' on the y and 'wavelength' on the x. it shows that the minimum wavelenth is produced wen intensity=0. how is this possible?
  16. C

    Quick Question regarding Atomic spectra

    An emission spectrum can contain wavelengths produced when an electron goes from the third to the second leve. So could you see this like in the absorption spectrum? Why?
  17. S

    Exploring the Invisible Spectra: What Can We See?

    Is it possible to see the radio spectra, X-ray, or microwave etc like birds can see the UV spectra? If so what might/does it look like? Thanks
  18. Link

    Interpreting Spectra for Jupiter's Rotational Speed

    I got a spectra I need to interpret. It is used to calculate the rotational speed of Jupiter. However, altough the computer indicates the doppler shift, I don't see anything (see photograph). I wonder if anyone could enlighten my stalled mind? :smile: I suppose when I figure out the...
  19. V

    Guide to NMR spectra notations/nomenclature needed

    Hello everyone. In the literature I come across spectra data as in the examples below: English example: 1H-NMR (CDCl3) δ: 1.09 (3H, t, CH3), 3.77 (3H, s, OCH3), 3.97-4.28 (2H, m, CH2), 4.28 (1H, s, CH) 6.41 (2H, t, pyrrole-H), 6.78 (2H, t, pyrrole-H), 7.13-7.21 (5H, m, ArH), 8.53 (1H, d...
  20. J

    Question on atomic spectra.

    I did a spectroscope experiment with a hydrogen discharge tube. So far I got this data: Line 1: Color=Red \lambda(nm)=700 \nu(Hz)=4.2*10^{14} n1=? n2=? \Delta{E}(J)=2.8*10^{-19} E(J)=? This is only the data for the Red line. I figured if i knew how to do this, I'll...
  21. B

    How can atomic spectra be only certin frequencies?

    I don't know a whole lot about quantum mechanics and there is something that dosen't make sense to me. An atom absorbes radiation in only certin frequencies. Do these frequencies have to be exact? Can they vary over a small range like say 1.000 to 1.001 or do they have to be perfectly exact...
  22. D

    What are reflectance spectra and synchronous spectra?

    What are reflectance spectra and synchronous spectra? What are the difference and which information I can obtain from them ?
  23. Y

    Testing Help w/ physics gre problem: radiation spectra

    64. Electromagnetic radiation provides a means to probe aspects of the physical universe. Which of the following statements regarding radiation spectra is NOT correct? a. lines in the infaret, visible, and ultraviolet regions of the spectrum reveal primarily the nuclear structure of the...
  24. C

    What Spectral Series Appear in the Absorption Spectrum of Ground State Hydrogen?

    When radiation with a continuous spectrum is passed through a volume of hydrogen gas whose atomes are all in the ground state, which spectral series will be present in the resulting absorption spectrum? Where do i even start?
  25. R

    What are potential terrestial acoustic zeitgebers?

    I'm looking for data on "acoustic noise" produced regularly by the earth, nothing man-made. In particular I'm looking for noise sources outside of the normal range of human hearing (20Hz-20kHz). Of course there are numerous terrestial noise sources, such as earthquake tremors, but those aren't...
  26. M

    Quantum Tunneling and atomic spectra.

    Can somebody explain quantum tunneling to me? And the thing about why amplitudes when they are trapped, the energies must choose from a distinct set of values? And why when particles that are totally free to wander will have any energy that they like? Also, why in the atomic spectra, more...
  27. E

    Find the Best NMR Spectra Interpretation Website

    there is this one really good NMR spectra interpretation website out there... i think. i vaguely remember coming across one years ago. anybody know what I am talking about? anybody know the url?
  28. H

    Exploring the Spectrum of Rings: Analytic & Differentiable Functions

    Spectrum of a Rings So I think I'm finally getting the definition of a scheme, but the texts I'm using aren't exactly ripe with examples. So, I wanted to condier some ring spectra to construct examples... I played around with the simple examples Z and Z[x], and my next thought was to look at...
  29. Hydr0matic

    Hydrogen Spectra: Lyman, Balmer, Paschen, Brackett Series

    Let me see if I got this straight... The hydrogen spectra consists of a couple of series - Lyman, Balmer, Paschen, Brackett, etc - which all corresponds to a certain energy transition - Lyman (n>1 -> n=1), Balmer (n>2 -> n=2).. and so on... correct ? And since n=1 is the ground state, a...
  30. jimmy p

    Classification of Stella Spectra

    Just a simple quickie, why are stars classified using the letters O, B, A, F, G, K and M? Is there any significance in the letters?
  31. N

    Interpreting UV absorption spectra

    hello all i'm investigating the band gap of certain nanocrystallites in the powder form, using a Shimadzu spectrometer with the powder dissolved in ethanol. The spectra, however, come with several peaks in addition to the expected peak for absorption. This is not unexpected as transitions to...
  32. B

    How Maxwell's theory of radiation could not explain atomic spectra?

    We all know that Maxwell did such a great work for all physicist. BUT, anyone knows that how Maxwell's theory of radiation could not explain atomic spectra?
  33. S

    Need image of absorption and emission spectra for sodium

    Hi, I need images of absorption and emission spectra for sodium to be used in a physics student book. Thanks in advance Stanley
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