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. R

    Explaining Hydrogen Atom's Line Spectra: The Rutherford Atomic Model

    Why the rutherford atomic model can't explain the line spectra of the hydrogen atom?
  2. N

    Solving Spectral Plotting Confusion with Hitran Database Data - Help Needed!

    I was not sure if I should post this here or in the Atomic forum (hope its in its right place). My task is to plot the "synthetic" emission spectra with help from data provided by the hitemp database (hitran database: http://www.cfa.harvard.edu/hitran/). So, I have several question that have...
  3. X

    Calculate energy level spectra?

    Recently, I read one book about quantum chaos. In it, random-matrix theory is used to describe the quantum signatures of chaos. Firstly, a new set of levels {E’1,E’2,E’3,...} is gained by unfolding the vibrational spectrum {E1,E2,E3,...}...
  4. D

    Identifying Spectra Using First & Second Order Lines

    I know there are many ways to identify the spectra but, what are the advantages and disadvantages of using the first and second order lines to identify spectra? Please Help! If u don't want give me answer then suggest me some links. Thanks
  5. R

    What is the Difference Between 1D Spectra and 2D Spectra?

    Hi, I am wondering what is the difference between 1D spectra and 2D spectra? I see many documents talking about one of these 2, but I couldn't find any clear definition...
  6. M

    Treating operators with continuous spectra as if they had actual eigenvectors?

    I'm trying to teach myself quantum mechanics from Dirac, and I'm having trouble justifying some of the maths, in particular how we can just jump out of the confines of a Hilbert space when it's convenient. Dirac rather liberally talks about observables that have a continuous range of...
  7. N

    Analyzing Power Spectra of Series: Frequency Scaling

    Homework Statement I am analyzing power spectrum of the series obtained using different approaches. I have 100 points series. First method is obtaining power spectrum by taking squared FT of series and divided by the period. Second method is taking IFT from ACVF of the series. In both cases...
  8. K

    Reading frequency spectrum / Fourier Transform and Power Spectra

    So I have a power spectrum of a given function, which is supposed to be a superposition of four sinusoidal terms with frequencies that range from 1xomega to 4xomega. My spectrum looks something like this: http://upload.wikimedia.org/wikipedia/commons/4/4f/Triangle-td_and_fd.png What exactly...
  9. S

    Print ViewBlackbody Radiation and Continuous Spectra

    Homework Statement An astronomer is trying to estimate the surface temperature of a star with a radius of 5.0* 10^8m by modeling it as an ideal blackbody. The astronomer has measured the intensity of radiation due to the star at a distance of 2.5* 10^{13}m and found it to be equal to 0.055...
  10. I

    Wich are the differences of the spectra of H and He ionized?

    Wich are the differences of the spectra of H and He ionized?
  11. L

    Relative Intensity in Spectra: What Does It Mean?

    Hi everyone, What does the "relative intensity" mean when we talk about spectra? The intensity relative to what, the background? Thank you
  12. S

    Intensity-wavelength graph for emission spectra; why is frequency in the x-axis?

    In my astrophysics book (Astrophysics, Nigel Ingham), there are intensity-wavelength graphs for line spectra (both emission & absorption). On the y-axis, relative intensity is plotted. But on the x-axis, frequency and not wavelength is plotted. Why is this? If I wanted to convert this graph to...
  13. E

    How to get spectra from a metal?

    Don't exactly know where to put this but how would one examine the spectra of a metal ore to find what is in it? That being, not using a mass spectrometre.
  14. I

    Find the spectra of most elements on line?

    Where could I find the spectra of most elements on line? I would expecially the He 2 spectrum, the Be and the B ones. Where could I find it?
  15. P

    Finding n for Line Spectra with 400 nm Wavelength

    I was given 400 nm. I was tasked to find n but i kept getting a value which is a not a integer. The value of n must be an integer right? 1/W = R(1/4 - 1/n^2) manipulate n=sqrt(4RW/RW-4) where R=1.097e7 n=6.752 I am thinking to make n as 6. But are there values of n greater than 5?
  16. I

    Atomic Isolation: Conditions for Line Spectra

    Hi Guys! *waves* Anyway, I was just wondering what conditions and in what state are atoms sufficiently isolated so that it gives rise to a line spectra. I thank you all for any help you provide in advance. Many thanks, Icetray
  17. A

    Product of spectra by diffraction gratings

    [b]1. Explain the physical principles of the production of spectra by diffraction gratings. include production of zero, first and second order spectrum. Homework Equations The Attempt at a Solution Diffraction and interference?
  18. E

    Emission Spectra: Learn & Explore Resources

    I don't really have a HW question, I am doing physics independent study and I have to do a project. My teacher suggested doing it about emission spectra, only, I have no idea what that is and searching EBSCO is not being really helpful, does anyone have any resources, ideas, etc where I could...
  19. N

    Wien's Law & Earth Emission Spectra: Investigating the discrepancy

    Hi, I have found several links using google to emission spectra of the Earth: http://lasp.colorado.edu/~bagenal/1010/SESSIONS/13.Light.html http://www.xylenepower.com/ http://spaceguard.esa.int/NScience/n...y/emission.htm All of which indicate a temperature of 280K and peak clearly at...
  20. N

    Wien's Displacement Law & Emission Spectra

    I have found several links using google to emission spectra of the Earth: http://lasp.colorado.edu/~bagenal/1010/SESSIONS/13.Light.html http://www.xylenepower.com/ http://spaceguard.esa.int/NScience/neo/dictionary/emission.htm All of which indicate a temperature of 280K and peak clearly...
  21. A

    Understanding Line Spectra: Evidence of Atomic Energy Levels

    Hello, can someone explain how a line spectrum works. How do they provide evidence of energy levels in atoms? I would have thought that energy levels are to do with a different concept of Bands (Valence, Conduction) so how does a line spectrum provide evidence? :confused:
  22. N

    Question about a Signal's Frequency Spectra and Modulation

    I used to think that the frequencies obtained by a Fourier Series or Transform from a signal in the 'time domain' were simply a consequence of our mathematical system. In other words, it is a consequence of the fact that sinusoids are used to recreate or synthesize the signal. It's just an...
  23. R

    Thick as a planck and making a spectra of myself

    for hv>>kT how does exp(hv/kT) compare to 1? I understand hv >>KT leads to an exponential fall in brightness but why did Planck introduce 1 in his equation. and only for values hv<<kT can this exponential be expanded! Thanks for any help!
  24. M

    Molecular Spectra: Solving Astronomy Problems

    I'm studying astronomy and I'm have these problems to solve, but there are a few things I don't really understand, hopefully someone can explain these things to me. 1. Why are spectra of molecules more complex than spectra of atoms? Is it because molecules can be excited in different ways...
  25. L

    Wavelength (Colours) and line spectra.

    1. How does wavelength affect line spectra (the spacing)? I did some research and found the wavelength of green light to be 510 nm and red light to be 650 nm. So for the experiment I looked through slits (such as 2, 2, 6 (which represents 2 slits, 2 points wide, and separated by 6 points)...
  26. S

    Questions on Line Spectra, Orbitals and Radiation

    I have several questions that I would appreciate if you guys could help me with, I want to understand these conepts as well as possible. In my chemistry textbook it states that the atoms of each element have a spectral signature, and each atom emits a certain wavelength of radiation, for...
  27. I

    Black lines in elements' emission spectra

    My understanding of analyzing emission spectra is that when the quantum number of an electron decreases (i.e. when it falls closer to the nucleus) it emits energy. I understand that this is a very basic understanding but I have not yet made it to college, so please bear with me. :) Now, what I...
  28. L

    Why LEDs Have a Broadened Spectra?

    Why is it that LEDs do not sharper spectra? I've been considering this recently, and was wondering if it was due to the uncertainty principle (like homogeneous broadening in a laser) or is it due to a fluctuating band gap? I've searched high and low and can't find any explanation for the...
  29. G

    Energy loss of spectra associated with Window Functions

    I'm doing research on window functions (such as: rectangular, Hanning, Blackman, etc), but am having trouble with respect to the energy loss associated with each. I know that applying the window causes energy loss in the spectra of interest, and for the Hanning Window and Hamming window...
  30. G

    Energy loss of spectra associated with Window Functions

    I'm doing research on window functions (such as: rectangular, Hanning, Blackman, etc), but am having trouble with respect to the energy loss associated with each. I know that applying the window causes energy loss in the spectra of interest, and for the Hanning Window and Hamming window...
  31. O

    Absorption Spectra: How is a Continuous Spectrum Possible?

    erm a simple question. If all light comes from the electrom-photon interference in an atom, that means that we can't obtain a continuous spectrum theoratically. How then is an absorption spectrum possible??
  32. M

    Demonstrating Tilted, Straight Lines in Rotating Sphere Spectra

    Homework Statement How do you show that in spectra taken along the equator of a rotating rigid sphere the spectral lines are tilted but straight? Homework Equations There were no equations given in the problem, so I guess you can use whatever equations you know. The Attempt at a...
  33. hagopbul

    Multiple lines in H2 and Hg emission spectra

    I was doing a test about rydberg constants using H2 and Hg light spectrum And in the spectrograph I found that H2 have three spectra and the Hg have 5 spectra And I DON'T KNOW WHY H2 have 3 lines and Hg have 5 lines? (Scientifically). I know it is the numbers of the electrons that...
  34. S

    Absorbtion/Emmision Spectra

    Homework Statement An atom of element Q can only absorb two photons of frequency 6.40E14 Hz and 9.05E14 Hz. Explain how atoms of element Q could absorb or emit photons of particular frequencies.2. The attempt at a solution OK I think I am missing something in my understanding of absorbtion...
  35. K

    Absorption Spectra - Questions & Answers from NZ High School Student

    Hello everyone, I'm new to this forum and in fact have never used a forum before so this is a bit new for me. I'm a high school student from NZ, and some of the course I'm doing has flummoxed -not in that I can't rattle off the generic answer, I just don't quite understand. The main area in...
  36. G

    Chemistry Spectra of small molecule and computed spectra

    Hi, I am calculating the spectra of a small molecule - benzen with nitrogen group attach. I have some experimental data of the molecule IR and raman. I use DFT B3LYP with TVZ as basis set when I compare the modes and are a lot of differences between the two. 1. Would it help to increase...
  37. G

    Interpreting IR/Raman Spectra Using Character Tables

    hi, I am trying to interpret some data which have been calculated for IR/Raman but I don't know how to interpret them exactly. The schema says mode \nu 1 b_u 82 1 a_g 216 2 b_g 239 I presume that the u/g are gerade/ungerade from the bonding/antibonding wave functions but how to...
  38. D

    What is the longest wavelength for ionizing ground state hydrogen atom?

    Homework Statement Is it possible to use electromagnetic radiation to ionize atoms. To do so, the atoms must absorb the radiation, the photons of which must have enough energy to remove an electron from an atom. What is the longest radiation wavelength (nm) that can be used to ionize the...
  39. I

    Rotational spectra - thermal population of rotational levels

    Homework Statement If the thermal population of the rotational levels is given by: Nj/No = (2J+1)*exp(-hcBJ(J+1)/kT) Calculate which state has the highest thermal population at a given temperature T. Calculation needs to be shown, not just a result. Homework Equations Nj/No =...
  40. G

    Fourier absorption spectra of Carbon monoxide

    So I have a spectra of CO that I need to interpret. My guess is that the spectra will depend on the vibrational and vibrational factors but how could I see that? I mean what will that come out like in the Fourier spectra? any tips on this our a site where I can read more about it is...
  41. C

    Will the spectra of the transmitted and received signal be different?

    Will the spectra of the transmitted and received signal be different as a result of multipath reflection and noise?
  42. B

    Atomic Spectra, transmission of photons

    Homework Statement A molecule with angular momentum L and moment of inertia I has a rotational energy that can be written as E=\frac{L^2}{2I}. Assuming that angular momentum is quantized according to Bohr's rule L = n\hbar, find the wavelength of the photons emitted in the n=2 to n=1...
  43. S

    Line Spectra of Li2+ & Be3+: Shortest Wavelength

    1. Doubly ionized lithium Li2+ (Z = 3) and triply ionized beryllium Be3+ (Z = 4) each emit a line spectrum. For a certain series of lines in the lithium spectrum, the shortest wavelength is 1222.2 nm. For the same series of lines in the beryllium spectrum, what is the shortest wavelength...
  44. H

    Taking 31P and 19F Spectra on Varian Unity Inova 500 MHz NMR

    Hi, We are using Varian Unity Inova 500 MHz NMR instrument.When we are taking 31P and 19F spectra we do not use any reference sample as like TMS etc. Our customer says us that they are not interpreting these spectras without reference. Which reference can we use for these spectras and how can...
  45. M

    Emission Spectra for Elements and Compounds

    Simply put, does it ever change? That is, does the line spectrum of a particular element or compound ever change? I've been searching all over, but I'm getting different answers! :grumpy:
  46. R

    Detecting Spectral Lines in Explosions

    Hi All, I am working on a sensitivity model for a short wave IR spectrometer. And I have come up to a few questions that I had never thought of before and that seem really interesting (and I still don't know the answers, so it'd be great if anyone had any insight!) Well, I need to look at an...
  47. E

    Emission spectra - predicting

    Hi there. I'm new to this board so please excuse if this is misplaced, there seems to be too many places to choose from. While browsing my computer I found a little program I wrote when doing year 12 physics that was based on the textbook material about ionization energies. It recurssively...
  48. A

    How many degenerate quantum states are there in the 3d state of a hydrogen atom?

    In the hydrogen atom, an electron is in the 3d state. (i) Find the orbital angular momentum of the electron (in units of n =3, l = n - 1, l = 1. L = [sqrt( l (l + 1) )]hbar therefore L = sqrt(2).hbar (ii) Find the energy of the electron (in eV). En = -13.6ev / n^2. E = - 13.6eV / 9 (iii)...
  49. G

    How can I open my IR spectra files without suitable software?

    I have tree files of IR spectra but I cann't open them, because I have no suitable software. I need to open them. does somebody knows some kind of freeware which I can use to open this files. or if somebody can I will send this files to open and copy them into MS Word and send them back to me...
  50. B

    Solving for n_1 and n_2 in Hydrogen Line Spectra

    I need help on this problem that asks me to solve for n_1 and n_2 (the initial and final quantum numbers). This is the given information (the line spectra for Hydrogen): color red known wavelength: 656.4 nm color turquoise known wavelength: 486.3 nm purple...
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